Primary human hepatocytes (PHH) are a main instrument in drug metabolism research and in the prediction of drug-induced phase I/II enzyme induction in humans. The HepG2 liver-derived cell line is commonly used as a surrogate for human hepatocytes, but their use in ADME and toxicity studies can be limited because of lowered basal levels of metabolizing enzymes. Despite their widespread use, the transcriptome of HepG2 cells compared to PHH is not well characterized. In this study, microarray analysis was conducted to ascertain the differences and similarities in mRNA expression between HepG2 cells and human hepatocytes before and after exposure to a panel of fluoroquinolone compounds. Comparison of the nave HepG2 cell and PHH transcriptomes revealed a substantial number of basal gene expression differences. When HepG2 cells were dosed with a series of fluoroquinolones, trovafloxacin, which has been associated with human idiosyncratic hepatotoxicity, induced substantially more gene expression changes than the other quinolones, similar to previous observations with PHH. While TVX-treatment resulted in many gene expression differences between HepG2 cells and PHH, there were also a number of TVX-induced commonalities, including genes involved in RNA processing and mitochondrial function. Taken together, these results provide insight for interpretation of results from drug metabolism and toxicity studies conducted with HepG2 cells in lieu of PHH, and could provide further insight into the mechanistic evaluation of TVX-induced hepatotoxicity.
Trovafloxacin-induced gene expression changes in liver-derived in vitro systems: comparison of primary human hepatocytes to HepG2 cells.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
AhR activation underlies the CYP1A autoinduction by A-998679 in rats.
Sex, Specimen part, Treatment
View SamplesMale Sprague-Dawley rats [Crl:CD(SD)IGS BR], weighing ~250 g at study initiation were obtained from Charles River Laboratories, Inc. (Wilmington, MA). Rats were housed singly in ventilated, stainless steel, wire-bottom hanging cages and fed non-certified Rodent Chow (Harlan Labs, Madison, WI) and water ad libitum and acclimated for at least 5 days after arrival. Rats were randomly assigned to various treatment groups (3 rats/group) and were dosed once daily by oral gavage with vehicle (0.2% hydroxypropylmethylcellulose at a dose volume of 10 ml/kg) or with 30, 100, or 200 mg/kg of A-998679. All rats were fasted overnight after their last dose, weighed and sacrificed under isoflurane anesthesia. Liver and small intestine (jejunum) were flash frozen in liquid nitrogen and stored at 80C until processing for gene expression profiling on the Affymetrix platform.
AhR activation underlies the CYP1A autoinduction by A-998679 in rats.
Sex, Specimen part
View SamplesMale Sprague-Dawley rats [Crl:CD(SD)IGS BR], weighing ~250 g at study initiation were obtained from Charles River Laboratories, Inc. (Wilmington, MA). Rats were housed singly in ventilated, stainless steel, wire-bottom hanging cages and fed non-certified Rodent Chow (Harlan Labs, Madison, WI) and water ad libitum and acclimated for at least 5 days after arrival. Rats were randomly assigned to various treatment groups (3 rats/group) and were dosed once daily by oral gavage with vehicle (0.2% hydroxypropylmethylcellulose at a dose volume of 10 ml/kg) or with 30, 100, or 200 mg/kg of A-998679. All rats were fasted overnight after their last dose, weighed and sacrificed under isoflurane anesthesia. Liver and small intestine (jejunum) were flash frozen in liquid nitrogen and stored at 80C until processing for gene expression profiling on the Affymetrix platform.
AhR activation underlies the CYP1A autoinduction by A-998679 in rats.
Sex, Specimen part, Treatment
View SamplesPurpose: Popular methods for library preparation in RNA-seq such as Illumina TruSeq® RNA v2 kit use a poly-A pulldown strategy. Such methods can cause loss of coverage at the 5’ end of genes, impacting the ability to detect fusions when used on degraded samples. The goal of this study was to quantify the effects RNA degradation has on fusion detection when using poly-A selected mRNA and to identify the variables involved in this process Methods: Total RNA was extracted from solid tumor tissue and whole blood using the Qiagen® miRNeasy Micro and Mini kits, respectively. The KU812 cell line was purchased from Sigma-Aldrich (St. Louis, MO) and UHR (Universal Human Reference RNA) was purchased from Agilent (Santa Clara, CA). UHR is a mixture of cell lines derived from breast adenocarcinoma, hepatoblastoma, cervix adenocarcinoma, testis embryonal carcinoma, gliobastoma, melanoma, liposarcoma, histiocytic lymphoma, lymphoblastic leukemia and plasmocytoma. For Degradation experiments, two micrograms of human universal reference RNA (UHR) (Agilent Technologies, Santa Clara, CA) and 1ug of RNA extracted from KU812 cell line (purchased from ATCC) were degraded at 74oC from 1 to 11 minutes in 1 minute intervals, using the NEBNext® Magnesium RNA Fragmentation Module Kit (NEB, Ipswich, MA). RNA was then purified and concentrated with RNeasy MinElute Cleanup Kit (Qiagen, Valencia, CA). Results: In this study, we designed experiments using artificially degraded RNA from cell lines as well as naturally degraded RNA from tissue samples to quantify the effect RNA degradation has on fusion detection when using poly-A selected RNA libraries We found that both the RNA degradation level and the distance from the 3’ end of a gene, negatively impact the read coverage profile in RNA-seq. Furthermore, the median transcript coverage decreases exponentially as a function of the distance from the 3’ end and there is a linear relationship between the coverage decay rate and the RNA integrity number (RIN). Conclusions: we found that when using poly-A pulldown techniques for library preparation in RNA-seq, the fusion sensitivity is negatively impacted by both sample degradation and distance of the fusion breakpoint from the 3’ end and developed graphs that show such effect. Such graphs can be useful in assessing the fusion sensitivity of RNA-seq in both research and clinical settings Overall design: Sequencing data was generated using Hiseq 2500 with a library of 101 paired end reads in the rapid run mode
Impact of RNA degradation on fusion detection by RNA-seq.
Disease, Subject
View SamplesThe goal is the characterization of the off-target activity of BKM120 observed in A2058 human melanoma cell line at IC90 concentration (3.606 M) but not at lower concentrations. Controls are BEZ235, GDC0941, showing no off-target activity.
Characterization of the mechanism of action of the pan class I PI3K inhibitor NVP-BKM120 across a broad range of concentrations.
Cell line
View SamplesIndividuals expressing alpha-1-antitrypsin mutant Z protein accumulate misfolded, mutant protein in the liver and are at risk for liver diseases including cirrhosis and hepatocellular carcinoma. Transgenic PiZ mice, a model for this liver disease, display similar pathologies to humans, including inflammation, increases in proliferation, autophagy and apoptosis, accumulation of globules and develop fibrosis and hepatocellular carcinoma with age. Microarrays were used to compare the gene expressions of PiZ mice to wild-type mice in order to identify the pathways that are altered in this disorder.
Oxidative stress contributes to liver damage in a murine model of alpha-1-antitrypsin deficiency.
Sex, Specimen part
View SamplesSplenic Transitional Type-1 B-cells from CBA wild-type mice, X-linked immunodeficiency mice and Bruton's tyrosine kinase knock-out mice. Two replicates where run on Affymetrix 420 2.0 arrays for CBA wild-type, Xid samples and the Btk KO samples.
Distinct gene expression signature in Btk-defective T1 B-cells.
Specimen part
View SamplesBruton's tyrosine kinase (Btk) is important for B lymphocyte development. To identify genes that are differentially expressed in primary B cells lacking functional Btk, splenocytes from X-linked immunodeficiency (Xid), Btk knockout (KO) and immunocompetent CBA mice, were used in microarrays containing more than 12,000 genes and expressed sequence tags (ESTs). We found 4515 transcripts expressed in duplicate experiments in all three strains. Out of these, 38 were differentially expressed genes (21 up-regulated >2 fold and 17 down-regulated <-2 fold) between CBA and Btk defective mice. Ten out of these genes were selected and quantitative Real-Time PCR was conducted for validation and further investigation. Real-Time experiments correlated nicely with the microarray data.
Gene expression profile of B cells from Xid mice and Btk knockout mice.
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Transcriptional signatures of Itk-deficient CD3+, CD4+ and CD8+ T-cells.
No sample metadata fields
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