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GSE57422
Homo sapiens
24 Downloadable Samples
Affymetrix Human Gene 2.1 ST Array (hugene21st)
Description
Erlotinib is a tyrosine kinase inhibitor (TKI) that is approved as a second-line monotherapy in patients with advanced non-small cell lung cancer (NSCLC). In these patients, erlotinib prolongs survival but its benefit remains modest since many tumors express wild-type EGF receptor (wtEGFR) lacking a TKI-sensitizing mutation, develop a second-site EGFR mutation, e.g., EGFR-L858R/T790M, or activate an alternate receptor tyrosine kinase, e.g., through MET amplification. To test potential drug combinations that could improve the efficacy of erlotinib, we combined erlotinib with quinacrine, which inhibits the FACT (facilitates chromatin transcription) complex that is required for nuclear factor-B (NF-B) transcriptional activity. In A549 (wtEGFR), H1975 (EGFR-L858R/T790M) and H1993 (MET amplification) NSCLC cells, the combination of erlotinib and quinacrine was highly synergistic, as quantified by Chou-Talalay combination indices. The combination inhibited colony formation, induced cell cycle arrest and apoptosis, and slowed xenograft tumor growth. Quinacrine decreased the level of active FACT subunit SSRP1 and suppressed NF-B-dependent luciferase activity. Knockdown of SSRP1 decreased cell growth and sensitized cells to erlotinib.
Publication Title
Quinacrine overcomes resistance to erlotinib by inhibiting FACT, NF-κB, and cell-cycle progression in non-small cell lung cancer.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 4 Downloadable Samples
Illumina HiSeq 2500
Description
Small molecule curaxin CBL0137 has broad anti-cancer activity in different preclinical models. It interferes with histone-DNA interactions via binding to DNA without causing DNA damage. It resposents first in class "chromatin damaging" agent without genotoxic properties. Its effect on the transcription in human tumor cells was evaluated. DNA-targeting small molecules are widely used for anticancer therapy based on their ability to induce cell death, presumably via DNA damage. DNA in the eukaryotic cell is packed into chromatin, a highly-ordered complex of DNA, histones, and non-histone proteins. These agents perturb chromatin organization. However, the mechanisms, consequences, and impact of the alterations of chromatin structure in relation to their anti-cancer activity is unclear because it is difficult to separate DNA damage and chromatin damage in cells. We recently demonstrated that curaxins, small molecules with broad anticancer activity, bind DNA without causing detectable DNA damage by interfering with histone/DNA interactions and destabilizing the nucleosome. Chromatin unfolding caused by curaxins is sensed by histone chaperone FACT. FACT binds unfolded nucleosomes, which leads to chromatin trapping or c-trapping. In this study, we investigated whether other DNA-targeting small molecules disturb chromatin and cause c-trapping. We found that only compounds directly binding DNA induce chromatin damage and c-trapping. Chromatin damage may occur in the absence of DNA damage and is dependent on the mechanism of compound binding to DNA and its ability to bind chromatinized DNA in cells. We show that FACT is sensitive to a plethora of nucleosomes perturbations induced by DNA-binding small molecules, including displacement of the linker histone, eviction of core histones, and accumulation of negative supercoiling. Most importantly, the cytotoxicity of DNA-binding small molecules correlates with their ability to cause chromatin damage , but not DNA damage. Overall design: HT1080 cells were treated with CBL0137 for 1 hour at 1uM. EU was added for the last 15 minutes. Newly synthesized RNA was isolated using Click-iTâ„¢ Nascent RNA Capture Kit (Invitrogen, cat#C10365) according to manufacturer instruction.
Publication Title
Prevention of Chromatin Destabilization by FACT Is Crucial for Malignant Transformation.
Sample Metadata Fields
Cell line, Subject
View Samples- Arabidopsis thaliana
- 4 Downloadable Samples
- Illumina Genome Analyzer II
Description
Backgropund:In a major paradigm shift in the last decade, the knowledge about a whole class of non-coding RNAs known as miRNAs has emerged, which have proved these to be important regulators of a wide range of cellular processes by the way of modulation of gene expression. It is reported that some of these miRNAs are modified by addition or deletion of nucleotides at their ends, after biogenesis. However, the biogenesis and functions of these modifications are not well studied in eukaryotes, especially in plants. In this study, we examined the miRNA modifications in different tissues of the various plants, namely rice, tomato and Arabidopsis and identified some common features of such modifications. Results:We have analyzed different aspects of miRNA modifications in plants. To achieve this end, we developed a PERL script to find the modifications in the sequences using small RNA deep sequencing data. The modification occurs in both mature and passenger (star) strands, as well as at both the 5'' and 3'' ends of miRNAs. Interestingly, we found a position-specific nucleotide biased modification, as evident by increased number of modification at the 5'' end with the presence of Cytosine (nucleotide ''C'') at the 3’end of the miRNA sequence. The level of modifications is not strictly dependent on the abundance of miRNA. Our study showed that the modification events are independent of plant species, tissue and physiological conditions. Our analysis also indicates that the RNAi enzyme, namely, the RNA dependent RNA polymerase 6 (RDR6) may not have any role in Arabidopsis miRNA modifications. Some of these modified miRNAs are bound to AGO1, suggesting their possible roles in biological processes. Conclusions:This is a first report that reveals that 5'' nucleotide additions are preferred for mature miRNA sequences with 3’ terminal ‘C’ nucleotide. Our analysis also indicates that the miRNAs modifications involving addition of nucleotides to the 5’ or 3’ end are independent of RDR6 activity and are not restricted by plant species, physiological conditions and tissue types. The results also indicate that such modifications might be important for biological processes. Overall design: small RNA profiles of wild type and RDR6 (-) of Arabidopsis plants were generated using deep sequencing data.
Publication Title
3' and 5' microRNA-end post-biogenesis modifications in plant transcriptomes: Evidences from small RNA next generation sequencing data analysis.
Sample Metadata Fields
Subject
View Samples- Rattus norvegicus
- 14 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Rats with adenine-induced chronic renal failure (A-CRF) develop a reduction in the rate of relaxation of the thoracic aorta. The primary aim of this study was to elucidate the mechanisms underlying this abnormality. Male Sprague-Dawley rats received either chow containing adenine or were pair-fed with normal chow (controls). After 8-14 weeks arterial functions were analyzed ex vivo using wire myography and the thoracic aorta was analyzed by DNA microarray.
Publication Title
Adenine-induced chronic renal failure in rats decreases aortic relaxation rate and alters expression of proteins involved in vascular smooth muscle calcium handling.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 9 Downloadable Samples
- Illumina HiSeq 2500
Description
RNA sequencing was performed to determine the uniqueness of splenic follicular IgD low B cells compared to splenic follicular IgD high and marginal zone B cells. Overall design: Splenic follicular IgD low and IgD high , and MZ B cells were sorted by FACS from naïve 8-10 weeks old mice. Total RNA was isolated from the sorted cells using RNAqueous® -4PCR kit and RNA sequencing was performed. Splenocytes from five mice were pooled for each sorting. Three independent sorting was performed for each B cell subset.
Publication Title
Mature IgD<sup>low/-</sup> B cells maintain tolerance by promoting regulatory T cell homeostasis.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus, Homo sapiens
- 4 Downloadable Samples
Affymetrix Human Gene 2.0 ST Array (hugene20st), Agilent-028005 SurePrint G3 Mouse GE 8x60K Microarray (Probe Name version)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Therapeutic targeting of the MYC signal by inhibition of histone chaperone FACT in neuroblastoma.
Sample Metadata Fields
Age, Specimen part, Cell line, Treatment
View Samples- Homo sapiens
- 2 Downloadable Samples
- Agilent-028005 SurePrint G3 Mouse GE 8x60K Microarray (Probe Name version), Affymetrix Human Gene 2.0 ST Array (hugene20st)
Description
Amplification of the MYCN oncogene predicts treatment resistance in childhood neuroblastoma. Using a MYC target gene signature that predicts poor neuroblastoma prognosis we identified the histone chaperone, FAcilitates Chromatin Transcription (FACT), as a crucial mediator of the MYC signal and a therapeutic target in the disease. FACT and MYCN expression created a forward feedback loop in neuroblastoma cells that was essential for maintaining mutual high expression. FACT inhibition by the small molecule Curaxin compound, CBL0137, markedly reduced tumor initiation and progression in vivo. CBL0137 exhibited strong synergy with chemotherapy in standard use by blocking repair of DNA damage caused by genotoxic drugs, thus creating a synthetic lethal environment in MYCN amplified neuroblastoma cells and a treatment strategy for MYCN-driven neuroblastoma
Publication Title
Therapeutic targeting of the MYC signal by inhibition of histone chaperone FACT in neuroblastoma.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 2 Downloadable Samples
- Affymetrix Human Gene 2.0 ST Array (hugene20st)
Description
Amplification of the MYCN oncogene predicts treatment resistance in childhood neuroblastoma. Using a MYC target gene signature that predicts poor neuroblastoma prognosis we identified the histone chaperone, FAcilitates Chromatin Transcription (FACT), as a crucial mediator of the MYC signal and a therapeutic target in the disease. FACT and MYCN expression created a forward feedback loop in neuroblastoma cells that was essential for maintaining mutual high expression. FACT inhibition by the small molecule Curaxin compound, CBL0137, markedly reduced tumor initiation and progression in vivo. CBL0137 exhibited strong synergy with chemotherapy in standard use by blocking repair of DNA damage caused by genotoxic drugs, thus creating a synthetic lethal environment in MYCN amplified neuroblastoma cells and a treatment strategy for MYCN-driven neuroblastoma
Publication Title
Therapeutic targeting of the MYC signal by inhibition of histone chaperone FACT in neuroblastoma.
Sample Metadata Fields
Cell line, Treatment
View Samples- Homo sapiens
- 36 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Hepatocellular carcinoma (HCC) is the fifth most-common cancer worldwide causing nearly 600,000 deaths esch year. Approximately 80% of HCC develops on the background of cirrhosis.It is necessary to identify novel genes involved in HCC to implement new diagnostic and treatment options. However, the molecular pathogenesis of HCC largely remains unsolved. Only a few genetic alterations, namely those affecting p53, -catenin and p16INK4a have been implicated at moderate frequencies of these cancers. Early detection of HCC with appropriate treatment can decrease tumor-related deaths
Publication Title
Genome-wide transcriptional reorganization associated with senescence-to-immortality switch during human hepatocellular carcinogenesis.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Cellular senescence is a tumor suppressor mechanism, and immortalization facilitates neoplastic transformation. Both mechanisms may be highly relevant to hepatocellular carcinoma (HCC) development and its molecular heterogeneity. Cellular senescence appears to play a major role in liver diseases. Chronic liver diseases are associated with progressive telomere shortening leading senescence that is observed highly in cirrhosis, but also in some HCC. We previously described the generation of immortal and senescence-programmed clones from HCC-derived Huh7 cell line.
Publication Title
Genome-wide transcriptional reorganization associated with senescence-to-immortality switch during human hepatocellular carcinogenesis.
Sample Metadata Fields
Sex, Specimen part
View Samples