Resistance of Calu3 NSCLC cells to the cytotoxic nucleoside analog gemcitabine (2',2'-difluorodeoxycytidine) can be prevented as well as reversed by the rexinoid X receptor selective agonist bexarotene. This study was designed to investigate the changes in gene expression associated with gemcitabine resistance and its reversal by bexarotene. In addition to the parental Calu3 cells and the 10 cycles of treatment of the gemcitabine resistant Calu3 cells with vehicle or bexarotene, analogous treatment paradigms with gemcitabine alone as well as the combination of both compounds have been included as controls. (However, it has to be noted that in the combination treatment, cells that were re-sensitized by bexarotene have largely been removed from the culture before harvest due to the cytotoxic activity of gemcitabine.)
Bexarotene (LGD1069, Targretin), a selective retinoid X receptor agonist, prevents and reverses gemcitabine resistance in NSCLC cells by modulating gene amplification.
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View SamplesInfection of the human host by Streptococcus pneumoniae begins with colonization of the nasopharynx, which is mediated by adherence of bacteria to respiratory epithelium. Several studies have indicated an important role for the pneumococcal capsule in this process. Here, we used microarrays to characterize the in vitro transcriptional response of human nasopharyngeal epithelial Detroit 562 cells to adherence of serotype 2-encapsulated strain D39, serotype 19F-encapsulated strain G54, serotype 4-encapsulated strain TIGR4, and their nonencapsulated derivatives (cps). In total, 322 genes were found to be upregulated in response to adherent pneumococci. Twenty-two genes were commonly induced, including those encoding several cytokines (e.g., IL-1, IL-6), chemokines (e.g., IL-8, CXCL1/2), and transcriptional regulators (e.g., FOS), consistent with an innate immune response mediated by Toll-like receptor signaling. Interestingly, 85% of genes was induced specifically by one or more encapsulated strains, suggestive of a capsule-dependent response. Importantly, purified capsular polysaccharides alone had no effect. Over a third of these loci encoded products predicted to be involved in transcriptional regulation and signal transduction, in particular MAPK signaling pathways. Real-time PCR of a subset of ten genes confirmed microarray data and showed a time-dependent upregulation of especially innate immunity genes. Downregulation of epithelial genes was most pronounced upon adherent D39cps, as 68% of the 161 genes identified was only repressed using this nonencapsulated strain. In conclusion, we identified a subset of host genes specifically induced by encapsulated strains during in vitro adherence, and have demonstrated the complexity of interactions occurring during the initial stages of pneumococcal infection.
Analysis of the in vitro transcriptional response of human pharyngeal epithelial cells to adherent Streptococcus pneumoniae: evidence for a distinct response to encapsulated strains.
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View SamplesThis SuperSeries is composed of the SubSeries listed below.
Nonadditive expression and parent-of-origin effects identified by microarray and allele-specific expression profiling of maize endosperm.
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View SamplesThe nuclear content of the plant endosperm is the result of the contribution two maternal genomes and a single paternal genome. This 2:1 dosage relationship provides a unique system for studying the additivity of gene expression levels in reciprocal hybrids. A combination of microarray profiling and allele-specific expression analysis was performed using RNA isolated from endosperm tissues of maize inbred lines B73 and Mo17 and their reciprocal hybrids at two developmental stages, 13 and 19 days after pollination. By assessing the relative levels of expression in the reciprocal hybrids it was possible to determine the prevalence of additive and non-additive expression patterns. While the majority of differentially expressed genes displayed additive expression patterns in the endosperm, approximately 10% of the genes displayed non-additive expression patterns including maternal-like, paternal-like, dominant high-parent, dominant low-parent and expression patterns outside the range of the inbreds. The frequency of hybrid expression patterns outside of the parental range in maize endosperm tissue is much higher than that observed for vegetative tissues. For a set of 90 genes allele-specific expression assays were employed to monitor allelic bias and regulatory variation. Eight of these genes exhibited evidence for maternally or paternally biased expression at multiple stages of endosperm development and are potential examples of differential imprinting. Collectively, our data indicate that parental effects on gene expression are much stronger in endosperm than in vegetative tissues, and that endosperm imprinting may be far more common than previously estimated.
Nonadditive expression and parent-of-origin effects identified by microarray and allele-specific expression profiling of maize endosperm.
No sample metadata fields
View SamplesThe nuclear content of the plant endosperm is the result of the contribution two maternal genomes and a single paternal genome. This 2:1 dosage relationship provides a unique system for studying the additivity of gene expression levels in reciprocal hybrids. A combination of microarray profiling and allele-specific expression analysis was performed using RNA isolated from endosperm tissues of maize inbred lines B73 and Mo17 and their reciprocal hybrids at two developmental stages, 13 and 19 days after pollination. By assessing the relative levels of expression in the reciprocal hybrids it was possible to determine the prevalence of additive and non-additive expression patterns. While the majority of differentially expressed genes displayed additive expression patterns in the endosperm, approximately 10% of the genes displayed non-additive expression patterns including maternal-like, paternal-like, dominant high-parent, dominant low-parent and expression patterns outside the range of the inbreds. The frequency of hybrid expression patterns outside of the parental range in maize endosperm tissue is much higher than that observed for vegetative tissues. For a set of 90 genes allele-specific expression assays were employed to monitor allelic bias and regulatory variation. Eight of these genes exhibited evidence for maternally or paternally biased expression at multiple stages of endosperm development and are potential examples of differential imprinting. Collectively, our data indicate that parental effects on gene expression are much stronger in endosperm than in vegetative tissues, and that endosperm imprinting may be far more common than previously estimated.
Nonadditive expression and parent-of-origin effects identified by microarray and allele-specific expression profiling of maize endosperm.
No sample metadata fields
View SamplesChronic liver injury triggers complications such as liver fibrosis and hepatocellular carcinoma (HCC), which are associated with alterations in distinct signaling pathways. Of particular interest is the interaction between mechanisms controlled by IKK/NEMO, the regulatory IKK subunit, and Jnk activation for directing cell death and survival. In the present study, we aimed to define the relevance of Jnk in hepatocyte-specific NEMO knockout mice (NEMOhepa), a genetic model of chronic inflammatory liver injury. We generated global Jnk1-/-/NEMOhepa and Jnk2-/-/NEMOhepa mice by crossing NEMOhepa mice with Jnk1-/- and Jnk2-/- animals, respectively, and examined the progression of chronic liver disease. Moreover, we investigated the expression of Jnk during acute liver injury, evaluated the role of Jnk1 in bone marrow-derived cells, and analyzed the expression of NEMO and pJnk in human diseased-livers. Deletion of Jnk1 significantly aggravated the progression of liver disease, exacerbating apoptosis, compensatory proliferation and carcinogenesis in NEMOhepa mice. Jnk2-/-/NEMOhepa showed increased RIP-1 and RIP-3 expression and hepatic inflammation. Jnk1 in hematopoietic cells rather than hepatocytes had an impact on the progression of chronic liver disease in NEMOhepa livers. These findings are of clinical relevance since NEMO expression was down-regulated in hepatocytes of patients with HCC whereas NEMO and pJnk were expressed in a large amount of infiltrating cells. While Jnk1 is protective in NEMOhepa-depleted hepatocytes, Jnk1 in hematopoietic cells rather than hepatocytes is a crucial driver of hepatic injury. These results elucidate the complex function of Jnk in chronic inflammatory liver disease.
Haematopoietic cell-derived Jnk1 is crucial for chronic inflammation and carcinogenesis in an experimental model of liver injury.
Sex, Age, Specimen part
View SamplesMegakaryoblastic Leukemia 1 and 2 (MKL1 and 2) are coactivators of the transcription factor Serum Response Factor (SRF). We recently showed that depletion of MKL1 and 2 abolished HCC xenograft growth, associated with oncogene-induced senescence. To identify suitable MKL target genes mediating these effects, we performed microarray analyses using HuH7 hepatocellular carcinoma cells stably expressing shRNA against MKL1/2 (HuH7 MKL1/2 KD). We therefore used a Affymetrix oligonucleotide array and filtered for genes whose expression in HuH7 MKL1/2 KD cells was reduced by a factor of at least 2.5 as compared to control HuH7 cells.
The novel MKL target gene myoferlin modulates expansion and senescence of hepatocellular carcinoma.
Specimen part
View SamplesHigh MC-SFA intake resulted in a downregulation of gene expression of pathways related to complement system and inflammation, and an upregulation of gene expression of pathways related to citric acid cycle, electron transport chain and lipid metabolism in adipose tissue. Based on our results, we hypothesize that the beneficial effects of MC-SFAs on prevention of fat accumulation may be mediated by increases in gene expression related to energy metabolism in the adipose tissue. Additionally, decreases in inflammation-related gene expression in the adipose may potentially have beneficial effects in relation to cardiometabolic diseases.
Dietary medium-chain saturated fatty acids induce gene expression of energy metabolism-related pathways in adipose tissue of abdominally obese subjects.
Sex, Age, Specimen part, Subject
View SamplesTo study the effect of Prnp genetic ablation on different aspects of RNA metabolism, we performed RNA sequencing of the hippocampus of wild-type C57BL/6J, congenic B6.129-PrnpZH1/ZH1 and coisogenic C57BL/6J-PrnpZH3/ZH3 mice. We analyzed differential gene expression, exon usage and RNA editing. Overall design: RNA sequencing on hippocampus of wild-type C57BL/6 mice, congenic B6.129-PrnpZH1/ZH1 and coisogenic C57BL/6-PrnpZH3/ZH3 mice (3 month-old males, n=4 per genotype).
Strictly co-isogenic C57BL/6J-Prnp-/- mice: A rigorous resource for prion science.
Sex, Age, Specimen part, Cell line, Subject
View SamplesFOXO transcription factors control cellular formation of reactive oxygen species (ROS), which critically contribute to cell survival and cell death in neuroblastoma. Here, we report that C10orf10, also named Decidual Protein induced by Progesterone (DEPP), is a direct transcriptional target of FOXO3 in human neuroblastoma. As FOXO3-mediated apoptosis involves a biphasic ROS accumulation, we analyzed cellular ROS levels in DEPP-knockdown cells by live-cell imaging. Knockdown of DEPP prevented the primary and secondary ROS accumulation during FOXO3 activation and attenuates FOXO3-induced apoptosis, whereas its overexpression raises cellular ROS levels and sensitizes to cell death. In neuronal cells, cellular steady state ROS are mainly detoxified in peroxisomes by the enzyme CAT/catalase. As DEPP contains a peroxisomal-targeting-signal-type-2 (PTS2) sequence at its N-terminus that enables protein import into peroxisomes, we analyzed the effect of DEPP on peroxisomal function by measuring the catalase enzyme activity. Catalase activity was reduced by conditional DEPP overexpression and significantly increased in DEPP-knockdown cells. Using live cell imaging and fluorescent peroxisomal and mitochondrial probes we demonstrate that DEPP localizes to peroxisomes and mitochondria in neuroblastoma cells. The combined data indicate that DEPP reduces peroxisomal activity and thereby impairs the cellular ROS detoxification capacity and contributes to death sensitization.
C10ORF10/DEPP, a transcriptional target of FOXO3, regulates ROS-sensitivity in human neuroblastoma.
Cell line, Treatment
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