In order to gain insight into the molecular pathogenesis of the myelodysplastic syndromes (MDS), we performed global gene expression profiling and pathway analysis on the hematopoietic stem cells (HSC) of 183 MDS patients as compared with the HSC of 17 healthy controls. The most significantly deregulated pathways in MDS include interferon signaling, thrombopoietin signaling and the Wnt pathway. Among the most significantly deregulated gene pathways in early MDS are immunodeficiency, apoptosis and chemokine signaling, whereas advanced MDS is characterized by deregulation of DNA damage response and checkpoint pathways. We have identified distinct gene expression profiles and deregulated gene pathways in patients with del(5q), trisomy 8 or 7/del(7q). Patients with trisomy 8 are characterized by deregulation of pathways involved in the immune response, patients with 7/del(7q) by pathways involved in cell survival, whilst patients with del(5q) show deregulation of integrin signaling and cell cycle regulation pathways. This is the first study to determine deregulated gene pathways and ontology groups in the HSC of a large group of MDS patients. The deregulated pathways identified are likely to be critical to the MDS HSC phenotype and give new insights into the molecular pathogenesis of this disorder thereby providing new targets for therapeutic intervention.
Deregulated gene expression pathways in myelodysplastic syndrome hematopoietic stem cells.
Specimen part, Disease
View SamplesThere still is a lack of specific, early markers for acute pancreatitis.
RCAN1 is a marker of oxidative stress, induced in acute pancreatitis.
No sample metadata fields
View SamplesTestosterone is necessary for the development of male pattern baldness, known as androgenetic alopecia (AGA); yet the mechanisms for decreased hair growth in this disorder are unclear. Here, we show that prostaglandin D2 synthase (PTGDS) is elevated at the mRNA and protein levels in bald scalp compared to haired scalp of men with AGA. The product of PTGDS enzyme activity, prostaglandin D2 (PGD2), is similarly elevated in bald scalp. During normal follicle cycling in mice Ptgds and PGD2 levels increase immediately preceding the regression phase, suggesting an inhibitory effect on hair growth. We show that PGD2 inhibits hair growth in explanted human hair follicles and when applied topically to mice. Hair growth inhibition requires the PGD2 receptor G protein-coupled receptor 44 (GPR44), but not the prostaglandin D2 receptor 1(PTGDR). Furthermore, we find that a transgenic mouse, K14-Ptgs2, which targets prostaglandin-endoperoxide synthase 2 expression to the skin, demonstrates elevated levels of PGD2 in the skin and develops alopecia, follicular miniaturization and sebaceous gland hyperplasia, which are all hallmarks of human AGA. These results define PGD2 as an inhibitor of hair growth in AGA and suggest the PGD2-GPR44 pathway as a potential target for treatment.
Prostaglandin D2 inhibits hair growth and is elevated in bald scalp of men with androgenetic alopecia.
Specimen part, Subject
View SamplesBackground. Differential gene expression in adipose tissue during diet-induced weight loss followed by a weight stability period is not well characterized. Markers of these processes may provide a deeper understanding of the underlying mechanisms. Objective. To identify differentially expressed genes in human adipose tissue during weight loss and weight maintenance after weight loss. Design. RNA from subcutaneous abdominal adipose tissue from nine obese subjects was obtained and analyzed at baseline, after weight reduction on a low calorie diet (LCD), and after a period of group therapy in order to maintain weight stability. Results. Subjects lost 18.8 + 5.4% of their body weight during the LCD and maintained this weight during group therapy. Insulin sensitivity (HOMA) improved after weight loss with no further improvement during weight maintenance. Cyclin-dependent kinase inhibitor 2B (CDKN2B) and JAZF zinc finger 1 (JAZF1), associated with type 2 diabetes, were downregulated. We could also confirm the downregulation of candidates for obesity and related traits, such as tenomodulin (TNMD) and matrix metallopeptidase 9 (MMP9), with weight loss. The expression of other candidates, such as cell death-inducing DFFA-like effector A (CIDEA) and stearoyl-CoA desaturase (SCD) were upregulated during weight loss but returned to baseline levels during weight maintenance. Conclusion. Genes in the adipose tissue are differentially expressed during weight loss and weight maintenance after weight loss. Genes that show sustained regulation may be of potential interest as markers of the beneficial effects of weight loss whereas others seem to be primarily involved in the process of weight loss itself.
Differential gene expression in adipose tissue from obese human subjects during weight loss and weight maintenance.
Sex, Age
View SamplesThe pathogenic mechanisms of common kidney glomerular diseases, including the vast majority of cases of proteinuria, remain unknown.
Glomerular transcriptome changes associated with lipopolysaccharide-induced proteinuria.
No sample metadata fields
View SamplesAt least 30 types of retinal ganglion cell (RGC) send distinct messages through the optic nerve to the brain. Strategies for promoting regeneration of RGC axons following injury act on only some of these types. Here we tested the hypothesis that over-expressing developmentally important transcription factors in adult RGCs could reprogram them to a “youthful” growth-competent state and promote regeneration of other types. From a screen of transcription factors expressed by developing RGCs, we found one, Sox11, that induced substantial axon regeneration. Transcriptome profiling confirmed that Sox11 activates genes involved in cytoskeletal remodeling and axon growth. Remarkably, alpha-RGCs, which preferentially regenerate following treatments such as PTEN deletion, were killed by Sox 11. Thus, Sox 11 promotes regeneration of non-alpha RGCs, which are refractory to PTEN. We conclude that Sox11 can reprogram adult RGCs to a growth-competent state and that different growth-promoting interventions act on distinct neuronal types. Overall design: We compared transcriptomes of retinal ganglion cells between AAV-Control retinas, and retinas treated with AAV-Sox11 overexpression. We then performed optic nerve crush, and 3 days later purified RGCs using FACS. RGCs were marked with Thy1-PE-Cy7 antibody and with live/dead cell staining. We performed sample preparations in full triplicate, and in each replicate we always performed Control and Sox11 on the same day, in alternating order.
Sox11 Expression Promotes Regeneration of Some Retinal Ganglion Cell Types but Kills Others.
Specimen part, Subject
View SamplesAtopic dermatitis (AD) is a common inflammatory skin disease with underlying defects in epidermal function and immune responses. The goal of this study was to investigate differences in gene expression in lesional skin from patients with mild extrinsic or intrinsic AD compared to skin from healthy controls and from lesional psoriasis skin. The aim was to identify differentially expressed genes involved in skin barrier formation and inflammation, and to compare our results with those reported for patients with moderate and severe AD.
Distinct molecular signatures of mild extrinsic and intrinsic atopic dermatitis.
Specimen part, Disease
View SamplesExamine global gene expression patterns in control and 35S:PAP1 Arabidopsis plants upon environmental perturbation (light and temperature) over the course of the experiments.
Environmental regulation of leaf colour in red 35S:PAP1 Arabidopsis thaliana.
No sample metadata fields
View SamplesThe expression levels of many genes show wide natural variation among strains or populations. This study investigated the potential for animal strain-related genotypic differences to confound gene expression profiles in acute cellular rejection (ACR). Additional analysis allowed for selection of 49 candidate genes uniquely associated with ACR, but only after accounting for the unexpectedly large effect of animal strain. Studies of ACR that examine gene expression in peripheral blood may be confounded by strain differences. These results indicate the need for study designs that eliminate or control for the large effect of genetic background on the transcriptome of immune cells.
Impact of animal strain on gene expression in a rat model of acute cardiac rejection.
Specimen part
View SamplesNovel approaches were used to generate the DNA sequence information for the rhesus GeneChip (2005). The purpose of this experiment was to test its reliability and validity of the rhesus macaque GeneChip across different tissues and centers.
Intercenter reliability and validity of the rhesus macaque GeneChip.
Specimen part, Cell line
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