Comparative analysis of gene expression in cultured primary keratinocytes isolated from newborn control (K14-cre; GPx4fl/+) and knockout (K14-cre; GPx4fl/fl) mice.
Targeted disruption of glutathione peroxidase 4 in mouse skin epithelial cells impairs postnatal hair follicle morphogenesis that is partially rescued through inhibition of COX-2.
Specimen part
View SamplesMET expression is elevated in a majority of human skin cancers but its contributions to pathogenesis have not been evaluated. In a mouse model of constitutive overexpression of HGF (MT-HGF), the incidence of squamous cell skin tumors induced by initiation with 7,12-dimethylbenz(a)anthracene (DMBA) followed by exposure to 12-O-tetradecanoyl-phorbol-13-acetate (TPA) is increased fivefold over control groups. Half of these tumors carry Hras1 or Kras mutations. Without DMBA initiation, tumors also erupt on MT-HGF mouse skin but only when TPA promotion is enhanced by crossing these mice with mice overexpressing cutaneous PKC. None of these tumors have Ras mutations. In culture, MT-HGF keratinocytes share identical MET mediated phenotypic and biochemical features with wildtype keratinocytes transformed by oncogenic RAS. In both cell types, these common features of initiated keratinocytes arise from autocrine activation of EGFR through elevated expression and release of EGFR ligands. Inhibition of EGFR ablates the initiated signature of MT-HGF keratinocytes in vitro and causes regression of MT-HGF induced tumors in vivo. Global gene expression data indicate that MT-HGF and RAS transformed keratinocytes share largely an identical profile of over 5000 mRNAs. Gene ontology analysis reveals the most affected concordant signature is enriched for functions relevant to tissue development and response to wounding, accompanied by cytokine and growth factor activity, and peptidase and endopeptidase activity previously not linked to initiated keratinocytes. Furthermore, gene co-expression analysis in skin cancer patients revealed a core RAS/MET co-expression network considerably activated in pre cancerous and cancerous lesions. Thus MET activation though EGFR contributes to human cutaneous cancers, and inhibitors could be efficacious in advanced lesions such as those seen in transplant recipient patients.
MET signaling in keratinocytes activates EGFR and initiates squamous carcinogenesis.
Specimen part
View SamplesTotal RNA was isolated from HuH-7 cells after transfection of IGF-II specific siRNAs. Gene expression profiling was performed using the Affymetrix Human Genome U133A 2.0 Arrays. The raw data were analysed using mixed model ANOVA.
Autocrine insulin-like growth factor-II stimulation of tumor cell migration is a progression step in human hepatocarcinogenesis.
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View SamplesThe effect of cyclic mecanical stretch on cardiac gene expression was studied in neonatal rat ventricular myocytes (NRVMs).
Mechanical stretch induced transcriptomic profiles in cardiac myocytes.
Treatment
View SamplesLeft ventricular gene expression profiles from 12-, 16- and 20-months old spontaneously hypertensive rats (SHRs) were compared with left ventricular profiles seen in age-matched Wistar-Kyoto (WKY) rats by screening Affymetrix U34A arrays (there are 4 samples in each timepoint except 3 samples of 20-months old WKYs).
Distinct upregulation of extracellular matrix genes in transition from hypertrophy to hypertensive heart failure.
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View SamplesMitogen-activated protein kinases (MAPKs) regulate cardiomyocyte growth and apoptosis in response to extracellular stimulation, but the downstream effectors that mediate their pathophysiological effects remain poorly understood. We determined the targets and role of p38 MAPK in the heart in vivo by using local adenovirus-mediated gene transfer of constitutively active upstream kinase mitogen-activated protein kinase kinase 3b (MKK3bE) and wild-type p38 in rats. DNA microarray analysis of animals with cardiac-specific overexpression of p38 MAPK revealed that 264 genes were upregulated more than 2-fold including multiple genes controlling cell division, cell signaling, inflammation, adhesion and transcription. Several previously unknown p38 target genes were found. Using gel mobility shift assays we identified several cardiac transcription factors that were directly activated by p38 MAPK. Finally, we determined the functional significance of the altered cardiac gene expression profile by histological analysis and echocardiographic measurements, which indicated that p38 MAPK overexpression induced gene expression results in cell proliferation, myocardial inflammation and fibrosis. In conclusion, we defined the novel target genes and transcription factors as well as the functional effects of p38 MAPK in the heart. Expression profiling of p38 MAPK overexpression identified cell cycle regulatory and inflammatory genes critical for pathological processes in the adult heart.
Identification of cell cycle regulatory and inflammatory genes as predominant targets of p38 mitogen-activated protein kinase in the heart.
Sex, Specimen part
View SamplesGene expression in placenta from 5 smoking and 5 non-smoking mothers analyzed by Affymetrix Hg133_plus2 microarrays.
Microarray analysis of the global alterations in the gene expression in the placentas from cigarette-smoking mothers.
No sample metadata fields
View SamplesThe objective of the study was to find cardiac GATA-4 target genes by overexpressing GATA-4 transcription factor in the left ventricle by adenoviral gene transfer.
GATA-4 is an angiogenic survival factor of the infarcted heart.
Sex, Specimen part
View SamplesThe prevalence of obesity has been increasing rapidly worldwide during the past two decades. This is alarming, since obesity has considerable effects on morbidity and mortality. The majority of gene expression studies about the effect of obesity and weight loss have been performed using the adipose tissue for mRNA extraction. However, also the liver plays a central role in maintaining energy balance. To our knowledge, no overall analysis of hepatic gene expression in response to changes in nutritional status has been made in humans Therefore, it is important to investigate how a short-time hypocaloric diet affects overall hepatic gene expression and the metabolic profile in a group of overweight and obese women. The subjects (n=31) were middle-aged, overweight (BMI>25 kg/m2) women with gallstone disease scheduled for an elective gallbladder operation. The intervention subjects were placed on a hypocaloric AHA step I diet with a recommended daily energy intake of 5.0 MJ. The objective was to reduce 0.5 kg of body weight per week. The control subjects were instructed to continue their habitual diet and not to lose weight. Basic clinical measurements and laboratory analyses were performed twice at baseline and at two week intervals during the weight reduction period. Surgical liver biopsies were obtained at the end of the weight reduction period. RNA samples of 4 individuals from the intervention group and 4 individuals from the control group were selected for the microarray analysis. The results from the microarray analysis were fairly surprising. Only one gene was up-regulated and the rest 142 down-regulated in the diet intervention group compared to the control group when a minimum of 2-fold change was set as the limit. The global decrease in hepatic gene expression was unexpected but the results are interesting, with several genes not previously linked to weight reduction. The decrease in triglyceride and fasting plasma insulin concentrations observed in our study is in accordance with results from many previous weight-loss trials.
The effect of a short-term hypocaloric diet on liver gene expression and metabolic risk factors in obese women.
No sample metadata fields
View SamplesThe effect of prototypical pregnane receptor X (PXR) agonist (pregnenolone 16-carbonitrile) PCN on hepatic gene expression was studied in mice primary hepatocytes.
Activation of nuclear receptor PXR impairs glucose tolerance and dysregulates GLUT2 expression and subcellular localization in liver.
Sex, Treatment
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