p53 is a frequent target for mutation in human tumors and previous studies have revealed that these missense mutant proteins can actively contribute to tumorigenesis. To elucidate how mutant p53 might contribute to mammary carcinogenesis we employed a three-dimensional (3D) culture model. In 3D culture non-malignant breast epithelial cells form structures reminiscent of acinar structures found in vivo, whereas breast cancer cells form highly disorganized and in some cases invasive structures. We found that mutant p53 depletion is sufficient to phenotypically revert breast cancer cells to a more acinar-like morphology. Genome-wide expression analysis identified the sterol biosynthesis, or mevalonate, pathway as significantly upregulated by a tumor-derived mutant p53. Using statins and sterol biosynthesis intermediates, we demonstrate that this pathway is both necessary and sufficient for the phenotypic effects of mutant p53 on breast tissue architecture. Mutant p53 associates with the sterol gene promoters at least partly via the SREBP transcription factors. Finally, p53 mutation correlates with higher levels of sterol biosynthesis genes in human breast tumors. This activity of mutant p53 not only contributes insight into breast carcinogenesis, but also implicates the mevalonate pathway as a new therapeutic target for tumors bearing such mutations in p53.
Mutant p53 disrupts mammary tissue architecture via the mevalonate pathway.
Specimen part, Cell line
View SamplesWe used microarrays to detail gene expression changes in Hs 294T human melanoma cells after treatment with elesclomol alone, or in combination with paclitaxel, to aide in identifing the mechnism of action of elesclomol.
Elesclomol induces cancer cell apoptosis through oxidative stress.
No sample metadata fields
View SamplesWe used microarrays to detail gene expression changes in Hs 294T human melanoma cells after treatment with elesclomol alone, or in combination with NAC, to aide in identifing the mechnism of action of elesclomol.
Elesclomol induces cancer cell apoptosis through oxidative stress.
No sample metadata fields
View SamplesDuring activation, T cells integrate multiple signals from APCs and cytokine milieu. The blockade of these signals can have clinical benefits as exemplified by CTLA4-Ig, which blocks interaction of B7 co-stimulatory molecules on APCs with CD28 on T cells. Variants of CTLA4-Ig, abatacept and belatacept are FDA approved as immunosuppressive agents in arthritis and transplantation whereas murine studies suggested that CTLA4-Ig can be beneficial in a number of other diseases. However, detailed analysis of human CD4 cell hyporesponsivness induced by CTLA4-Ig has not been performed. Herein, we established a model to study effect of CTLA4-Ig on the activation of human naïve T cells in a human mixed lymphocytes system. Comparison of human CD4 cells activated in the presence or absence of CTLA4-Ig, showed that co-stimulation blockade during TCR activation does not affect NFAT signaling but results in decreased activation of NF-kB and AP-1 transcription factors followed by profound decrease in proliferation and cytokine production. The resulting T cells become hyporesponsive to secondary activation and, although capable of receiving TCR signals, fail to proliferate or produce cytokines, demonstrating properties of anergic cells. However, unlike some models of T cell anergy, these cells did not possess increased levels of TCR signaling inhibitor CBLB. Rather, the CTLA4-Ig induced hyporesponsiveness was associated with an elevated level of p27kip1 cyclin-dependent kinase inhibitor. Overall design: Time series. Human resting and activated T cell dUTP mRNA-Seq profiles were generated on Illumina HiSeq2500
Functional characterization of human T cell hyporesponsiveness induced by CTLA4-Ig.
No sample metadata fields
View SamplesThe development of CRISPR-Cas systems for targeting DNA and RNA in diverse organisms has transformed biotechnology and biological research. Moreover, the CRISPR revolution has highlighted bacterial adaptive immune systems as a rich and largely unexplored frontier for discovery of new genome engineering technologies. In particular, the class 2 CRISPR-Cas systems, which use single RNA-guided DNA-targeting nucleases such as Cas9, have been widely applied for targeting DNA sequences in eukaryotic genomes. Here, we report DNA-targeting and transcriptional control with class I CRISPR-Cas systems. Specifically, we repurpose the effector complex from type I variants of class 1 CRISPR-Cas systems, the most prevalent CRISPR loci in nature, that target DNA via a multi-component RNA-guided complex termed Cascade. We validate Cascade expression, complex formation, and nuclear localization in human cells and demonstrate programmable CRISPR RNA (crRNA)-mediated targeting of specific loci in the human genome. By tethering transactivation domains to Cascade, we modulate the expression of targeted chromosomal genes in both human cells and plants. This study expands the toolbox for engineering eukaryotic genomes and establishes Cascade as a novel CRISPR-based technology for targeted eukaryotic gene regulation. Overall design: Examination of transcriptome-wide changes in gene expression with Cascade-mediated activation of endogenous genes.
Targeted transcriptional modulation with type I CRISPR-Cas systems in human cells.
Specimen part, Cell line, Subject
View SamplesGametogenesis is dependent on the expression of germline-specific genes. However, it remains unknown how the germline epigenome is distinctly established from that of somatic lineages. Here we show that genes commonly expressed in somatic lineages and spermatogenesis-progenitor cells undergo repression in a genome-wide manner in late stages of the male germline and identify underlying mechanisms. SCML2, a germline-specific subunit of a Polycomb repressive complex 1 (PRC1), establishes the unique epigenome of the male germline through two distinct antithetical mechanisms. SCML2 works with PRC1 and promotes RNF2-dependent ubiquitination of H2A, thereby marking somatic/progenitor genes on autosomes for repression. Paradoxically, SCML2 also prevents RNF2-dependent ubiquitination of H2A on sex chromosomes during meiosis, thereby enabling unique epigenetic programming of sex chromosomes for male reproduction. Our results reveal divergent mechanisms involving a shared regulator by which the male germline epigenome is distinguished from that of the soma and progenitor cells. Overall design: RNA-seq and ChIP-seq analyses using wild-type and Scml2-KO spermatogenic cells
Poised chromatin and bivalent domains facilitate the mitosis-to-meiosis transition in the male germline.
No sample metadata fields
View SamplesPrevalence and severity of allergic diseases have increased worldwide. To date, respiratory allergy phenotypes are not fully characterized and, in addition, the mechanisms underlying sublingual immunotherapy (SLIT) are still unknown.
Exploring novel systemic biomarker approaches in grass-pollen sublingual immunotherapy using omics.
Specimen part, Treatment, Time
View SamplesThe activation profiles of macrophages under different immune and inflammatory conditions have generated great interest. LPS, in particular, is a commonly used in vitro model of infection and inflammation studies in macrophages. We have used gene expression microarrays to define the effects of each of three variables; LPS dose, LPS vs. interferons beta and gamma, and genetic background on the transcriptional response of mouse bone marrow-derived macrophages
Analysis of the transcriptional networks underpinning the activation of murine macrophages by inflammatory mediators.
No sample metadata fields
View SamplesTemporal changes of gene expression from 1-wk- to 5-wk-old rat in kidney and lung, and the effect of prior growth inhibition on these genetic changes.
Coordinated postnatal down-regulation of multiple growth-promoting genes: evidence for a genetic program limiting organ growth.
Age, Specimen part
View SamplesThe purpose of this study was to investigate whether paternal high-fat diet (HFD) transgenerationally remodeled the hepatic transcriptome of F2 female rats
Paternal high-fat diet transgenerationally impacts hepatic immunometabolism.
Sex, Specimen part
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