Global transcriptome patterns were determined in XVE-14 and wild-type seedlings induced for 45 min b-estradiol in order to identify the genes early regulated by EBE transcription factor.
EBE, an AP2/ERF transcription factor highly expressed in proliferating cells, affects shoot architecture in Arabidopsis.
Specimen part
View SamplesThe aim was to identify early target genes of the senescence-associated transcription factor: ORS1. For this purpose we used DEX-inducible system and studied the expression profile 5h after treatment using Affymetrix microarray.
ORS1, an H₂O₂-responsive NAC transcription factor, controls senescence in Arabidopsis thaliana.
Specimen part
View SamplesSoft tissue sarcomas are a diverse set of fatal human tumors where few agents have demonstrable clinical efficacy, with the standard therapeutic combination of doxorubicin and ifosfamide showing only a 25-30% response rate in large multi-institutional trials. Although liposarcomas are the most common histological form of adult soft tissue sarcomas, research in this area is severely hampered by the lack of experimentally tractable in vitro model systems. To this end, here we describe a novel in vitro model for human pleomorphic liposarcoma. The cell line (LS2) is derived from a pleomorphic liposarcoma that utilizes Alternative Lengthening of Telomeres (ALT) mechanism of telomere maintenance, which may be particularly important in modulating the response of this tumor type to DNA damaging agents. We present detailed baseline molecular and genomic data, including genome wide copy number and transcriptome profiles, for this model compared to its parental tumor and a panel of liposarcomas covering multiple histologies. The model has retained essentially all of the detectable alterations in copy number that are seen in the parental tumor, and shows molecular karyotypic and expression profiles consistent with pleomorphic liposarcomas. We also demonstrate the utility of this model, together with two additional human liposarcoma cell lines, to investigate the relationship between topoisomerase 2A expression and the sensitivity of ALT-positive liposarcomas to doxorubicin. This model, together with its associated baseline data, provide a powerful new tool to develop treatments for this clinically poorly-tractable tumor, and to investigate the contribution that ALT makes to modulating sensitivity to DNA damaging chemotherapeutic agents such as doxorubicin.
Doxorubicin resistance in a novel in vitro model of human pleomorphic liposarcoma associated with alternative lengthening of telomeres.
Cell line
View SamplesA gene expression signature purporting to distinguish between telomerase and ALT immortalization has recently been described (Lafferty-Whyte et al., 2009). This was obtained as the intersection of two independent signatures, one obtained from cell lines and the other from a panel of liposarcomas, which utilize different telomere maintenance mechanisms (TMMs). To assess the utility of this signature we used Affymetrix U133plus2.0 arrays to undertake a similar analysis of an independent collection of liposarcomas of defined TMM. In our dataset, the 297 gene signature causes the liposarcomas to cluster not on the basis of TMM, but rather on the basis of tumor histological subtype [Figure 1], consistent with the signatures reported by others (Matushansky et al., 2008).
Validating a gene expression signature proposed to differentiate liposarcomas that use different telomere maintenance mechanisms.
No sample metadata fields
View SamplesRationale: Obstructive sleep apnea (OSA) has been associated with a number of chronic disorders that may improve with effective therapy. However, the molecular pathways affected by continuous positive airway pressure (CPAP) treatment are largely unknown. We sought to assess the system-wide consequences of CPAP therapy by transcriptionally profiling peripheral blood leukocytes (PBLs). Methods: Subjects diagnosed with severe OSA were treated with CPAP, and whole-genome expression measurement of PBLs was performed at baseline and following therapy. We used Gene Set Enrichment Analysis (GSEA) to identify gene sets that were differentially enriched. Network analysis was then applied to identify key drivers of pathways influenced by CPAP. Results: 18 subjects with severe OSA (apnea hypopnea index 30 events/hour) underwent CPAP therapy and microarray analysis of their PBLs. Treatment with CPAP improved AHI, daytime sleepiness and blood pressure but did not affect anthropometric measures. GSEA revealed a number of enriched gene sets, many of which were involved in neoplastic processes and displayed down-regulated expression patterns in response to CPAP. Network analysis identified several densely connected genes that are important modulators of cancer and tumor growth. Conclusions: Effective therapy of OSA with CPAP is associated with alterations in circulating leukocyte gene expression. Functional enrichment and network analyses highlighted transcriptional suppression in cancer-related pathways suggesting potentially novel mechanisms linking OSA with neoplastic signatures.
Treatment of obstructive sleep apnea alters cancer-associated transcriptional signatures in circulating leukocytes.
Treatment, Subject
View SamplesObstructive sleep apnea (OSA) has been linked to dysregulated metabolic states and treatment of sleep apnea may improve these conditions. Subcutaneous adipose tissue is a readily samplable fat depot that plays an important role in regulating metabolism. However, neither the pathophysiologic consequences of OSA nor the effects of continuous positive airway pressure (CPAP) in altering this compartment’s molecular pathways are understood. This study aimed to systematically identify subcutaneous adipose tissue transcriptional programs modulated in OSA and in response to its effective treatment with CPAP. Two subject groups were investigated: Study Group 1 was comprised of 10 OSA and 8 controls; Study Group 2 included 24 individuals with OSA studied at baseline and following CPAP. For each subject, genome-wide gene expression measurement of subcutaneous fat was performed. Differentially activated pathways elicited by OSA (Group 1) and in response to its treatment (Group 2) were determined using network and Gene Set Enrichment Analysis (GSEA). In Group 2, treatment of OSA with CPAP improved apnea hypopnea index, daytime sleepiness, and blood pressure, but not anthropometric measures. In Group 1, GSEA revealed many up-regulated gene sets in OSA subjects, most of which were involved in immuno-inflammatory (e.g., interferon-γ signaling), transcription, and metabolic processes such as adipogenesis. Unexpectedly, CPAP therapy in Group 2 subjects was also associated with up-regulation of several immune pathways as well as cholesterol biosynthesis. Collectively, our findings demonstrate that OSA alters distinct inflammatory and metabolic programs in subcutaneous fat, but these transcriptional signatures are not reversed with short-term effective therapy.
Obstructive sleep apnea and CPAP therapy alter distinct transcriptional programs in subcutaneous fat tissue.
Sex, Age
View SamplesWe used microarrays to identify genes regulated during oncolytic HSV infection. Oncolytic herpes simplex viruses (oHSV) are promising anticancer therapeutics. We sought to identify alterations in gene expression during oHSV infection of human cancer cells. Human malignant peripheral nerve sheath tumor (MPNST) cells were infected with G207, an ICP34.5-deleted oHSV previously evaluated in clinical trials. G207-infected cells demonstrated massive degradation of cellular mRNAs, while a subset were upregulated. A gene signature of 21 oHSV-induced genes contained 7 genes known to be HSV-induced. Go ontology classification revealed that a majority of upregulated genes are involved in Jak/STAT signaling, transcriptional regulation, nucleic acid metabolism, protein synthesis and apoptosis. Ingenuity-defined functional networks highlighted nodes for AP-1 subunits and interferon signaling via STAT1, SOCS1, SOCS3 and RANTES. Upregulation of SOCS1 correlated with sensitivity of MPNST lines to G207 and depletion of SOCS1 reduced virus replication >1-log. The transcriptome of oHSV-induced genes may predict oncolytic efficacy and provides rationale for next generation oncolytics.
Molecular analysis of human cancer cells infected by an oncolytic HSV-1 reveals multiple upregulated cellular genes and a role for SOCS1 in virus replication.
No sample metadata fields
View SamplesThe embryo lethal adenosine methylase tDNA knockout line SALK_074069 was partially complemented with its cDNA driven by the embryo specific ABI3 promoter (A6 lines). The plants have reduced adenosine methylation and show pleiotropic phenotypes. Rosette leaves were harvested from 3 week old plants, both wild-type and mutant plants in triplicate and analysed using the Affymetrix ATH1 array.
Adenosine Methylation in Arabidopsis mRNA is Associated with the 3' End and Reduced Levels Cause Developmental Defects.
Age, Specimen part
View SamplesIn Alzheimers disease (AD), early deficits in learning and memory are a consequence of synaptic modification which are likely induced by toxic beta-amyloid oligomers (oA). To identify molecular targets downstream of oA binding we prepared synaptoneurosomes from frontal cortex of control and IAD patients, and isolated mRNAs for comparison of gene expression. This approach elevated synaptic mRNAs above the threshold necessary for expression changes to be discriminated and also reduced other cellular mRNAs. In patients with minimal cognitive impairment (MCI) termed incipient AD (IAD) global measures of cognition declined with increasing levels of dimeric A (dA). These patients also showed increased expression of neuroplasticity related genes, many encoding 3' UTR consensus sequences that regulate local translation in the synapse. One such gene, GluR2, displayed elevated mRNA and protein expression in IAD. Other neurotransmitter-related genes were also upregulated. Overexpressed genes may induce compensatory as well as negative effects on cognition and provide targets for intervention to moderate the response to dA.
Transcriptome analysis of synaptoneurosomes identifies neuroplasticity genes overexpressed in incipient Alzheimer's disease.
No sample metadata fields
View SamplesTo identify genes heretofore undiscovered as critical players in the biogenesis of teeth, we have used microarray gene expression analysis of the developing mouse molar tooth (DMT) between 1 and 10 days postnatal to identify genes differentially expressed when compared to 16 control tissues (GEO accession # GSE1986). Of the top 100 genes exhibiting increased expression in the DMT, 29 were found to have been previously associated with tooth development. Differential expression of the remaining 71 genes not previously associated with tooth development was confirmed by qRT-PCR analysis. Further analysis of seven of the latter genes by mRNA in situ hybridization found that five were specific to the developing tooth in the craniofacial region (Rspo4, Papln, Amtn, Gja1, Maf). Of the remaining two, one was found to be more widely expressed (Sp7) and the other was found to be specific to the nasal serous gland, which is close to, but distinct from, the developing tooth (Vrm).
Identification of novel genes expressed during mouse tooth development by microarray gene expression analysis.
Sex, Specimen part
View Samples