Statins are widely used cholesterol-lowering drugs that inhibit HMG-CoA reductase, a key enzyme in cholesterol synthesis. In some cases, however, these drugs may cause a number of toxic side effects in hepatocytes and skeletal muscle tissue. Currently, the specific molecular mechanisms that cause these adverse effects are not sufficiently understood. In this work, genome-wide RNA expression changes in primary human hepatocytes of six individuals were measured at five time points upon atorvastatin treatment. A novel systems-level analysis workflow was applied to reconstruct regulatory mechanisms based on these drug-response data and available knowledge about transcription factor binding specificities, protein-protein interactions and protein-drug interactions. Several previously unknown transcription factors, regulatory cofactors and signaling molecules were found to be involved in atorvastatin-responsive gene expression. Some novel relationships, e.g., the regulatory influence of nuclear receptor NR2C2 on CYP3A4, were successfully validated in wet-lab experiments.
Inferring statin-induced gene regulatory relationships in primary human hepatocytes.
Specimen part, Treatment, Subject
View SamplesAcinar cells make up the majority of all cells in the pancreas, yet the source of new acinar cells during homeostasis remains unknown. Using multicolor lineage-tracing and organoid-formation assays, we identified the presence of a progenitor-like acinar cell subpopulation. These cells have long-term self-renewal capacity, albeit in a unipotent fashion. We further demonstrate that binuclear acinar cells are terminally differentiated acinar cells. Transcriptome analysis of single acinar cells revealed the existence of a minor population of cells expressing progenitor markers. Interestingly, a gain of the identified markers accompanied by a transient gain of proliferation was observed following chemically induced pancreatitis. Altogether, our study identifies a functionally and molecularly distinct acinar subpopulation and thus transforms our understanding of the acinar cell compartment as a pool of equipotent secretory cells. Overall design: The single-cell RNA-seq library preparation protocol was based on the SMART seq2 protocol (Picelli et al., 2014) with following modifications. Acinar cells were isolated as described in the section Acinar Cell Isolation and Culture and resuspended in DPBS without Ca2+ and Mg2+ (PAN-Biotech). Cells were collected in a volume of 0.5 µL and transferred to a reaction tube containing 4 µL of 6 M guanidine-HCl (Sigma-Aldrich), 0.1% (v/v) Triton X-100 (Sigma-Aldrich) and 1% (v/v) 2-mercaptoethanol (?Sigma-Aldrich). The tube was immediately transferred into liquid nitrogen and kept there for the duration of cell collection. Next, 2.2× RNA SPRI beads (Beckman Coulter) were added directly to the lysis buffer and incubated for 5 min at room temperature. The beads were washed twice with 70% ethanol. Air-dried beads were resuspended in a solution containing 2 µL of H20, 1 µL of oligo(dT) primer, and 1 µL of dNTP Mix (primer and nucleotides used as in Picelli et al., 2014). Twenty-four cells contained ERCC Spike-In RNAs (1:10,000; Mix2, Ambion) Mix in addition to primer and nucleotides. Beads were incubated for 3 min at 72°C, and reverse transcription and PCR (19 cycles) were performed as described by Picelli et al. (2014). PCR product was cleaned up using 0.8× DNA SPRI beads (Beckman Coulter), and air-dried beads were resuspended in 15 µL of H2O. The quality of cDNA library was assessed for each cell on a high-sensitivity DNA Bioanalyzer chip. Subsequent steps (tagmentation, amplification, multiplexing) were done as previously described (Llorens-Bobadilla et al., 2015). The DKFZ Genomics and Proteomics Core Facility conducted sequencing on an Illumina HiSeq2000 sequencer (paired-end 100 bp).
Single-Cell Analysis Uncovers Clonal Acinar Cell Heterogeneity in the Adult Pancreas.
Sex, Specimen part, Cell line, Subject
View SamplesDiffuse large B-cell lymphoma (DLBCL) represents a heterogeneous diagnostic category with distinct molecular subtypes that can be defined by gene expression profiling. However, even within these defined subtypes, heterogeneity prevails. To further elucidate the pathogenesis of these entities, we determined the expression of the tumor suppressor phosphatase and tensin homolog (PTEN) in 248 primary DLBCL patient samples. These analyses revealed that loss of PTEN was detectable in 55% of germinal center B-cell-like (GCB) DLBCLs, whereas this abnormality was found in only 14% of non-GCB DLBCL patient samples. In GCB DLBCL, the PTEN status was inversely correlated with activation of the oncogenic PI3K/ protein kinase B (AKT) pathway in both DLBCL cell lines and primary patient samples. Re-expression of PTEN induced cytotoxicity in PTEN-deficient GCB DLBCL cell line models by inhibiting PI3K/AKT signaling, indicating an addiction to this pathway in this subset of GCB DLBCLs. PI3K/AKT inhibition induced down-regulation of the transcription factor MYC. Re-expression of MYC rescued GCB DLBCL cells from PTEN-induced toxicity, identifying a regulatory mechanism of MYC expression in DLBCL. Finally, pharmacologic PI3K inhibition resulted in toxicity selectively in PTEN-deficient GCB DLBCL lines. Collectively, our results indicate that PTEN loss defines a PI3K/ AKT-dependent GCB DLBCL subtype that is addicted to PI3K and MYC signaling and suggest that pharmacologic inhibition of PI3K might represent a promising therapeutic approach in these lymphomas.
PTEN loss defines a PI3K/AKT pathway-dependent germinal center subtype of diffuse large B-cell lymphoma.
Sex, Disease, Cell line, Treatment
View SamplesA prospective study was conducted in the Neonatal Intensive Care Unit of the University Children's hospital between September 1, 2008 and November 30, 2010. The entry criteria were (1) preterm birth below 32 weeks gestational age, (2) birthweight<1500g (VLBW). During the follow-up period, bronchopulmonary dysplasia (BPD) was diagnosed in 68 (61%) infants, including 40 (36%) children with mild disease, 13 (12%) with moderate and 15 (13%) with severe BPD. Forty-three babies served as a control group (no BPD).
Gene expression profiling in preterm infants: new aspects of bronchopulmonary dysplasia development.
Sex, Specimen part
View SamplesWe report the profiling of induced mRNA transcripts in two C. elegan replicate populations -- WT (N2) and mutant strain with deficient HLH30. Both strains were fed either OP50 strain of e-coli (normal feed) or S. aureus Overall design: Examination of infected versus uninfected wildtype and mutant lawns of animals
Innate host defense requires TFEB-mediated transcription of cytoprotective and antimicrobial genes.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
IκB-ζ controls the constitutive NF-κB target gene network and survival of ABC DLBCL.
Cell line, Treatment
View SamplesConstitutive activation of the nuclear factor-kappa B (NF-kB) pathway is a hallmark of the activated B-cell-like (ABC) subtype of diffuse large B-cell lymphoma (DLBCL). Recurrent mutations of NF-kB regulators that cause constitutive activity of this oncogenic pathway have been identified. However, it remains unclear how specific target genes are regulated. We identified the IkB-like protein NFKBIZ that binds NF-kB subunits and enhances transactivation of some NF-kB target genes while repressing others, to be upregulated in ACB compared to GCB DLBCL primary patient samples (p=5.1 x 10^-37). Knockdown of NFKBIZ by RNA interference was toxic to ABC but not GCB DLBCL cell lines. Gene expression profiling following NFKBIZ knockdown significantly downregulated a large number of NF-kB target genes, suggesting a central role in regulating NF-kB signaling. To further investigate the molecular mechanisms of how NFKBIZ mediates NF-kB signaling in ABC DLBCL, we performed immunoprecipitations and detected an interaction of NFKBIZ with both p50 and p52 NF-kB subunits, indicating that both the canonical and non-canonical NF-kB pathways are regulated by NFKBIZ. Collectively, our data imply that NFKBIZ is required for NF-kB signaling in ABC DLBCL and thus might represent a promising molecular target for future therapies.
IκB-ζ controls the constitutive NF-κB target gene network and survival of ABC DLBCL.
Cell line
View SamplesConstitutive activation of the nuclear factor-kappa B (NF-kB) pathway is a hallmark of the activated B-cell-like (ABC) subtype of diffuse large B-cell lymphoma (DLBCL). Recurrent mutations of NF-kB regulators that cause constitutive activity of this oncogenic pathway have been identified. However, it remains unclear how specific target genes are regulated. We identified the IkB-like protein NFKBIZ that binds NF-kB subunits and enhances transactivation of some NF-kB target genes while repressing others, to be upregulated in ACB compared to GCB DLBCL primary patient samples (p=5.1 x 10^-37). Knockdown of NFKBIZ by RNA interference was toxic to ABC but not GCB DLBCL cell lines. Gene expression profiling following NFKBIZ knockdown significantly downregulated a large number of NF-kB target genes, suggesting a central role in regulating NF-kB signaling. To further investigate the molecular mechanisms of how NFKBIZ mediates NF-kB signaling in ABC DLBCL, we performed immunoprecipitations and detected an interaction of NFKBIZ with both p50 and p52 NF-kB subunits, indicating that both the canonical and non-canonical NF-kB pathways are regulated by NFKBIZ. Collectively, our data imply that NFKBIZ is required for NF-kB signaling in ABC DLBCL and thus might represent a promising molecular target for future therapies.
IκB-ζ controls the constitutive NF-κB target gene network and survival of ABC DLBCL.
Cell line, Treatment
View SamplesPerinatal asphyxia is detrimental to the newborn baby and the use of supplemental oxygen during resuscitation may worsen the prognosis of these babies. The mechanism behind hyperoxic injury is not fully understood and our aim was to investigate four oxygen therapies following hypoxia and these effects on transcriptional activity.
Transcriptome profiling of the newborn mouse brain after hypoxia-reoxygenation: hyperoxic reoxygenation induces inflammatory and energy failure responsive genes.
Specimen part
View SamplesRIP-chip-SRM : a New Combinatorial Large Scale Approach Identifies a Set of Translationally Regulated bantam/miR 58 Targets in C. elegans
RIP-chip-SRM--a new combinatorial large-scale approach identifies a set of translationally regulated bantam/miR-58 targets in C. elegans.
Specimen part
View Samples