This experiment series addresses the role of coactivator SRC-1/NcoA-1 for the induction of interleukin-6 (IL-6) target genes in HepG2 cells. For that purpose, HepG2 human hepatocellular carcinoma cells were manipulated to stably express an shRNA that knocks down SRC-1 expression yielding the HepG2-Src1 cells. Either unmanipulated HepG2 or HepG2-Src1 cells were then treated for various periods with IL-6.
Co-activator SRC-1 is dispensable for transcriptional control by STAT3.
No sample metadata fields
View SamplesBackground: Septic shock is a heterogeneous syndrome within which probably exist several biological subclasses. Discovery and identification of septic shock subclasses could provide the foundation for the design of more specifically targeted therapies. Herein we tested the hypothesis that pediatric septic shock subclasses can be discovered through genome-wide expression profiling. Methods: Genome-wide expression profiling was conducted using whole blood-derived RNA from 98 children with septic shock, followed by a series of bioinformatic approaches targeted at subclass discovery and characterization. Results: Three putative subclasses (subclasses A, B, and C) were initially identified based on an empiric, discovery-oriented expression filter and unsupervised hierarchical clustering. Statistical comparison of the 3 putative subclasses (ANOVA, Bonferonni correction, p < 0.05) identified 6,934 differentially regulated genes. K means clustering of these 6,934 genes generated 10 coordinately regulated gene clusters corresponding to multiple signaling and metabolic pathways, all of which were differentially regulated across the 3 subclasses. Leave one out cross validation procedures indentified 100 genes having the strongest predictive values for subclass identification. Forty-four of these 100 genes corresponded to signaling pathways relevant to the adaptive immune system and glucocorticoid receptor signaling, the majority of which were repressed in subclass A patients. Subclass A patients were also characterized by repression of genes corresponding to zinc-related biology. Phenotypic analyses revealed that subclass A patients were younger, had a higher illness severity, and a higher mortality rate than patients in subclasses B and C. Conclusions: Genome-wide expression profiling can identify pediatric septic shock subclasses having clinically relevant phenotypes.
Identification of pediatric septic shock subclasses based on genome-wide expression profiling.
Age, Specimen part, Disease, Disease stage
View SamplesBackground: Septic shock heterogeneity has important implications for the conduct of clinical trials and individual patient management. We previously addressed this heterogeneity by indentifying 3 putative subclasses of children with septic shock based on a 100-gene expression signature corresponding to adaptive immunity and glucocorticoid receptor signaling. Herein we attempted to prospectively validate the existence of these gene expression-based subclasses in a validation cohort. Methods: Gene expression mosaics were generated from the 100 class-defining genes for 82 individual patients in the validation cohort. Patients were classified into 1 of 3 subclasses (A, B, or C) based on color and pattern similarity relative to reference mosaics generated from the original derivation cohort. Separate classifications were conducted by 21 individual clinicians and a computer-based algorithm. After subclassification the clinical database was mined for clinical phenotyping. Results: In the final consensus subclassification generated by clinicians, subclass A patients had a higher illness severity, as measured by illness severity scores and maximal organ failure, relative to subclasses B and C. The k coefficient across all possible inter-evaluator comparisons was 0.633. Similar observations were made based on the computer-generated subclassification. Patients in subclass A were also characterized by repression of a large number of genes having functional annotations related to zinc biology. Conclusions: We have validated the existence of subclasses of children with septic shock based on a biologically relevant, 100-gene expression signature. The subclasses can be indentified by clinicians without formal bioinformatics training, at a clinically relevant time point, and have clinically relevant phenotypic differences.
The influence of developmental age on the early transcriptomic response of children with septic shock.
Age, Specimen part, Disease, Disease stage
View SamplesIn an ongoing translational research program involving microarray-based expression profiles in pediatric septic shock, we have now conducted longitudinal studies focused on the temporal expression profiles of canonical signaling pathways and gene networks. Genome-level expression profiles were generated from whole blood-derived RNA samples of children with septic shock (n = 30 individual patients) corresponding to days 1 and 3 of admission to the pediatric intensive care unit. Based on sequential statistical and expression filters, day 1 and day 3 of septic shock were characterized by differential regulation of 2,142 and 2,504 gene probes, respectively, relative to normal control patients. Venn analysis demonstrated 239 unique genes in the day 1 data set, 598 unique genes in the day 3 data set, and 1,906 genes common to both data sets. Analyses targeted toward derivation of biological function from these data sets demonstrated time-dependent, differential regulation of genes involved in multiple canonical signaling pathways and gene networks primarily related to immunity and inflammation. Notably, multiple and distinct gene networks involving T cell- and MHC antigen-related biological processes were persistently downregulated from day 1 to day 3. Further analyses demonstrated large scale and persistent downregulation of genes corresponding to functional annotations related to zinc homeostasis. These data represent the largest reported cohort of patients with septic shock, which has undergone longitudinal genome-level expression profiling. The data further advance our genome-level understanding of pediatric septic shock and support novel hypotheses that can be readily tested at both the experimental and translational levels.
Genome-level longitudinal expression of signaling pathways and gene networks in pediatric septic shock.
No sample metadata fields
View SamplesNormal children, children with SIRS, children with sepsis, and children with septic shock.
Genomic expression profiling across the pediatric systemic inflammatory response syndrome, sepsis, and septic shock spectrum.
No sample metadata fields
View SamplesRationale: We previously generated genome-wide expression data in children with septic shock, based on whole blood-derive RNA, having the potential to lead the field into novel areas of investigation.
Validating the genomic signature of pediatric septic shock.
Sex
View SamplesGoal of the experiment: To identify correlated genes, pathways and groups of patients with systemic inflammatory response syndrome and septic shock that is indicative of biologically important processes active in these patients.
Genome-level expression profiles in pediatric septic shock indicate a role for altered zinc homeostasis in poor outcome.
No sample metadata fields
View SamplesAs susceptibility to many adult disorders originates in utero, we here hypothesized that fetal sex influences gene expression in placental cells and produces functional differences in human placentas. We found that fetal sex differentially affects gene expression in a cell-phenotype dependent manner among all four placental cell-phenotypes studied: cytotrophoblasts, syncytiotrophoblasts, arterial endothelial cells and venous endothelial cells. The markedly enriched pathways in males were identified to be signaling pathways for graft-versus-host disease as well as the immune and inflammatory systems, both supporting the hypothesis that there is reduced maternal-fetal compatibility for male fetuses.
The human placental sexome differs between trophoblast epithelium and villous vessel endothelium.
Sex, Specimen part
View SamplesWe hypothesized altered expression of Proteases in calls capable of physiological invasion vs angiogenesis. We analyzed trophoblasts isolated from first trimester placenta that are invasive, and placental endothelial cells, that gave a high angiogenic potential. We found different expression levels of most proteases.
Different Preference of Degradome in Invasion versus Angiogenesis.
Specimen part
View SamplesWe hypothesized that the trophoblast secretes anti-angiogenic factors, which increase in late pregnancy to limit angiogenesis. Therefore, we determined the paracrine effect of primary human trophoblasts from early versus late pregnancy on the angiogenic potential of isolated feto-placental endothelial cells.
Pigment epithelium-derived factor (PEDF): a novel trophoblast-derived factor limiting feto-placental angiogenesis in late pregnancy.
Specimen part
View Samples