Background: Isolation and characterization of tumourigenic colon cancer initiating cells may help to develop novel diagnostic and therapeutic procedures. Methods: We characterized a panel of fourteen human colon carcinoma cell lines and their corresponding xenografts for the surface expression of different potential stem cell markers: CD133, CD24, CD44, CDCP1 and CXCR4. In five cell lines and nine xenografts mRNA expression of the investigated markers was determined. Tumour growth behaviour of CD133+, CD133- and unsorted SW620 cells was evaluated in vivo. Results: All surface markers showed distinct expression patterns in the examined tumours. Analyses of the corresponding xenografts revealed a significant reduction of cell numbers expressing the investigated markers. CD44 and CXCR4 mRNA expression correlated within the cell line panel and CD44 and CDCP1 within the xenograft panel, respectively. Small subpopulations of double and triple positive cells could be described. SW620 showed significantly higher take rates and shorter doubling times in vivo when sorted for CD133 positivity. Conclusion: Our data support the hypothesis of a small subset of cells with stem cell-like properties characterized by a distinct surface marker profile. In vivo growth kinetics give strong relevance for an important role of CD133 within the mentioned surface marker profile.
Characterization of colon cancer cells: a functional approach characterizing CD133 as a potential stem cell marker.
Sex, Age, Specimen part
View SamplesDespite timely and successful surgery, 32% of patients with bilateral and 10% with unilateral cryptorchidism will develop azoospermia. Cryptorchid boys at risk of azoospermia display a typical testicular histology of impaired mini-puberty at the time of the orchidopexy.
Testicular gene expression in cryptorchid boys at risk of azoospermia.
Specimen part
View SamplesPancreatic cancer cells transduced with sh knockdown of GRP78 Overall design: Pancreatic cancer mRNA profiles of scrambled control versus shGRP78 cell line, in triplicate, using Illumina Truseq Stranded Total-RNA library
ER stress sensor, glucose regulatory protein 78 (GRP78) regulates redox status in pancreatic cancer thereby maintaining "stemness".
Specimen part, Cell line, Subject
View SamplesAberrant forms of the SWI/SNF chromatin remodeling complex are associated with human disease. Loss of the Snf5 subunit of SWI/SNF is a driver mutation in pediatric rhabdoid cancers and forms aberrant sub-complexes that are not well characterized. We determined the effects of loss of Snf5 on the composition, nucleosome binding, recruitment and remodeling activities of yeast SWI/SNF. The Snf5 subunit interacts with the ATPase domain of Snf2 and forms a submodule consisting of Snf5, Swp82 and Taf14 as shown by mapping SWI/SNF subunit interactions by crosslinking-mass spectrometry and subunit deletion followed by immunoaffinity chromatography. Snf5 promoted binding of the Snf2 ATPase domain to nucleosomal DNA, enhanced its catalytic activity and facilitated nucleosome remodeling. Snf5 was required for acidic transcription factors to recruit SWI/SNF to chromatin. RNA-seq analysis suggested that both the recruitment and catalytic functions mediated by Snf5 are required for SWI/SNF regulation of gene expression. Overall design: Determining the effects of loss of Snf5 on the composition, nucleosome binding, recruitment, remodeling activities and gene expression profile of yeast SWI/SNF
Loss of Snf5 Induces Formation of an Aberrant SWI/SNF Complex.
Cell line, Subject
View SamplesTo follow-up findings that miR-9 was abundantly expressed in control NPCs, significantly down-regulated in a subset of SZ NPCs, and that miR-9 levels/activity, neural migration and diagnosis were strongly correlated, we tested the effect of manipulating miR-9 at cellular, proteomic and transcriptomic levels. Unexpectedly, proteomic- and RNAseq-based analysis revealed that these effects were mediated primarily by small changes in expression of indirect miR-9 targets, rather than large changes in direct miR-9 targets; these indirect targets are enriched for migration-associated genes. Together these data indicate that aberrant levels and activity of miR-9 may be one of the many factors that contribute to SZ risk, at least in a subset of patients. Methods: We compared global transcription of forebrain NPCs from two control and two SZ patients with manipulated miR-9 levels by RNAseq. Results: Although RNAseq analysis revealed large inter-individual heterogeneity, we were able to resolve several functional consistencies in the effects of our miR-9 perturbations: i) the change in miR-9 activity was consistent with the inhibitory role of miR-9, ii) the gene expression fold-change of miR-9 target genes (between each perturbation and its corresponding control, summarized by the first principal component) was correlated (r=0.95, p=3.92e-04) with miR-9 fold change and iii) the differentially expressed (DE; p <0.01) gene list resulting from miR-9 perturbation (paired t-test) was enriched for miR-9 targets (1.53-fold, p=1.2e-5). Conclusions: We integrated the miR-9 perturbation RNAseq data with our existing RNAseq datasets contrasting control and SZ hiPSC NPC expression from our cohort 1 (six controls, four patients), to ask whether there was any relationship between the “SZ NPC signature” and “miR-9 perturbation” datasets; we observed that the DE (p-value <0.01) in “SZ NPC signature” is enriched for DE (fdr<0.01) in “miR-9 perturbation” (the overall enrichment is 2.31-fold (p=9.39e-09)); there is significant correlation between DE fold-change in these two datasets (overall genes r=0.188; p<10e-50). Effects were mediated primarily by small changes in expression of indirect miR-9 targets, rather than large changes in direct miR-9 targets; these indirect targets are enriched for migration-associated genes Overall design: Biological duplicates of passage-matched NPCs from 1 control (female) and 1 SZ patient (female) were transduced with either RV-GFP or RV-miR-9-GFP; GFP-positive NPCs were purified by fluorescent activated cell sorting (FACS) and expanded for two passages. In parallel, passage-matched NPCs from 2 controls (1 male, 1 female) and 2 SZ patients (1 male, 1 female) were transiently transfected with either scrambled or miR-9 LNA probes. In both instances, miR-9 perturbation was confirmed by qPCR.
Dysregulation of miRNA-9 in a Subset of Schizophrenia Patient-Derived Neural Progenitor Cells.
Sex, Specimen part, Disease, Subject
View SamplesCell-based models of many neurological and psychiatric diseases, established by reprogramming patient somatic cells into human induced pluripotent stem cells (hiPSCs), have now been reported. While numerous reports have demonstrated that neuronal cells differentiated from hiPSCs are electrophysiologically active mature neurons, the “age” of these cells relative to cells in the human brain remains unresolved. Comparisons of gene expression profiles of hiPSC-derived neural progenitor cells (NPCs) and neurons to the Allen BrainSpan Atlas indicate that hiPSC neural cells most resemble first trimester neural tissue. Consequently, we posit that hiPSC-derived neural cells may most accurately be used to model the early developmental defects that contribute to disease predisposition rather than the late features of the disease. Though the characteristic symptoms of schizophrenia SZ generally appear late in adolescence, it is now thought to be a neurodevelopmental condition, often predated by a prodromal period that can appear in early childhood. Postmortem studies of SZ brain tissue typically describe defects in mature neurons, such as reduced neuronal size and spine density in the prefrontal cortex and hippocampus, but abnormalities of neuronal organization, particularly in the cortex, have also been reported. We postulated that defects in cortical organization in SZ might result from abnormal migration of neural cells. To test this hypothesis, we directly reprogrammed fibroblasts from SZ patients into hiPSCs and subsequently differentiated these disorder-specific hiPSCs into NPCs. SZ hiPSC differentiated into forebrain NPCs have altered expression of a number of cellular adhesion genes and WNT signaling. Methods: We compared global transcription of forebrain NPCs from six control and four SZ patients by RNAseq. Results: Multi-dimensional scaling (MDS) resolved most SZ and control hiPSC NPC samples; 848 genes were significantly differentially expressed (FDR<0.01) Conclusions: The WNT signaling pathway was enriched 2-fold (fisher exact test p-value = 0.031). Overall design: 1-2 independent differentiations (biological replicates) for each of four control and four schizophrenia patients were analyzed; samples were generated in parallel to neuron RNAseq data.
Dysregulation of miRNA-9 in a Subset of Schizophrenia Patient-Derived Neural Progenitor Cells.
No sample metadata fields
View SamplesWe established several iPSCs from healthy donors, familial ALS (FALS) patients, and sporadic ALS (SALS) patients. Using our differentiation protocol originally developed, we differentiated these iPSCs toward spinal motor neurons (MNs) and reproduced ALS pathology in a dish.
Modeling sporadic ALS in iPSC-derived motor neurons identifies a potential therapeutic agent.
Specimen part, Disease, Treatment, Subject
View SamplesThe mechanisms regulating breast cancer differentiation state are poorly understood. Of particular interest are molecular regulators controlling the highly aggressive and poorly differentiated traits of basal-like breast carcinomas. Here we show that the Polycomb factor EZH2 maintains the differentiation state of basal-like breast cancer cells, and promotes the expression of progenitor-associated and basal-lineage genes. Specifically, EZH2 regulates the composition of basal-like breast cancer cell populations by promoting a bi-lineage differentiation state, in which cells co-express basal- and luminal-lineage markers. We show that human basal-like breast cancers contain a subpopulation of bi-lineage cells, and that EZH2-deficient cells give rise to tumors with a decreased proportion of such cells. Bi-lineage cells express genes that are active in normal luminal progenitors, and possess increased colony formation capacity, consistent with a primitive differentiation state. We found that GATA3, a driver of luminal differentiation, performs a function opposite to EZH2, acting to suppress bi-lineage identity and luminal progenitor gene expression. GATA3 levels increase upon EZH2 silencing, leading to the observed decrease in bi-lineage cell numbers. Our findings reveal a novel role for EZH2 in controlling basal-like breast cancer differentiation state and intra-tumoral cell composition.
EZH2 promotes a bi-lineage identity in basal-like breast cancer cells.
Specimen part, Cell line, Treatment
View SamplesThe nuclear receptor PPARalpha is recognized as the primary target of the fibrate class of hypolipidemic drugs and mediates lipid lowering in part by activating a transcriptional cascade that induces genes involved in the catabolism of lipids. We report here the characterization of three novel PPARalpha agonists with therapeutic potential for treating dyslipidemia. These structurally related compounds display potent and selective binding to human PPARalpha and support robust recruitment of coactivator peptides in vitro. These compounds markedly potentiate chimeric transcription systems in cell-based assays and strikingly lower serum triglycerides in vivo. The transcription networks induced by these selective PPARalpha agonists were assessed by transcriptional profiling of mouse liver after acute and chronic treatment. The induction of several known PPARalpha target genes involved with fatty acid metabolism were observed, reflecting the expected pharmacology associated with PPARalpha activation. We also noted the downregulation of a number of genes related to immune cell function, the acute phase response, and glucose metabolism; suggesting that these compounds may have anti-inflammatory action in the mammalian liver. Taken together, these studies articulate the therapeutic promise of a selective PPARalpha agonist.
Molecular characterization of novel and selective peroxisome proliferator-activated receptor alpha agonists with robust hypolipidemic activity in vivo.
No sample metadata fields
View SamplesOver expression of PDGF-C in mouse liver resulted in the progression of hepatic fibrosis, steatosis and the development of HCC; this mouse model closely resembles the human HCC that is frequently associated with hepatic fibrosis.
Acyclic retinoid targets platelet-derived growth factor signaling in the prevention of hepatic fibrosis and hepatocellular carcinoma development.
Specimen part
View Samples