Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Noncoding somatic and inherited single-nucleotide variants converge to promote ESR1 expression in breast cancer

ABSTRACT: Sustained expression of the estrogen receptor-Î± (ESR1) drives two-thirds of breast cancer and defines the ESR1-positive subtype. ESR1 engages enhancers upon estrogen stimulation to establish an oncogenic expression program1. Somatic copy number alterations involving the ESR1 gene occur in approximately 1 % of ESR1-positive breast cancers2â5, suggesting that other mechanisms underlie the persistent expression of ESR1. We report significant enrichment of somatic mutations within the set of regulatory elements (SRE) regulating ESR1 in 7% of ESR1-positive breast cancers. These mutations regulate ESR1 expression by modulating transcription factor binding to the DNA. The SRE includes a recurrently mutated enhancer whose activity is also affected by rs9383590, a functional inherited single-nucleotide variant (SNV) that accounts for several breast cancer riskâassociated loci. Our work highlights the importance of considering the combinatorial activity of regulatory elements as a single unit to delineate the impact of noncoding genetic alterations on single genes in cancer. RNA-Seq was performed in HCC1419 cells heterozygous for the functional SNV, rs9383590, to determine which genes displayed an allelic imbalance within a 1MB window.

ORGANISM(S): Homo sapiens

SUBMITTER: Mathieu Lupien

PROVIDER: E-GEOD-74718 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:Next-generation sequencing has revolutionized cancer biology by accelerating the unbiased discovery of novel mutations across human cancers. Transforming such discoveries into a conceptual framework of cancer progression requires narrowing the vast number of mutations down to the driver elements, and further reducing these to mutations that govern cancer progression as opposed to tumor initiation. By integrating next-generation RNA-sequencing (RNA-seq) with in vivo selection, we devise an approach that identifies a series of novel recurrent non-synonymous amino acid mutations that are enriched in metastatic breast cancer cells and predicted to significantly alter protein function. These mutations, found in PANX1, RBFA, REST, KRIT1 and ZSWIM6, are detected at higher frequencies in the transcriptomes of two patientsâ highly metastatic sub-lines relative to their poorly metastatic parental lines. We functionally characterize the cellular and molecular roles of one of these mutationsâa nonsense alteration that yields a truncated pannexin-1 (PANX11-89) plasma membrane megachannel subunitâin metastatic progression. PANX11-89 interacts with full-length PANX1 and augments PANX1 channel activity to promote the survival of cancer cells as they are mechanically deformed. Protection from deformation-induced cell death requires PANX1 channels to release ATP, which acts as a cell autonomous survival signal during mechanical stress. Functional characterization of additional nonsense and missense PANX1 mutations detected in epithelial cancers of the colon, lung, and prostate reveals that these mutants also enhance PANX1-mediated ATP release. In vivo testing of one such truncating mutation detected in a metastatic colorectal tumor also enhances early survival, dissemination and liver metastatic colonization by human colon cancer cells. Finally, pharmacological inhibition of PANX1 inhibits breast cancer metastasis, implicating PANX1 as a novel therapeutic target in cancer. Our findings reveal that ATP release through mechanosensitive PANX1 channels enables cancer cells to overcome a major metastasis suppressive barrier—deformation-induced death in the microvasculature. To systematically identify base-pair mutations present in metastatic cells that may drive cancer progression, we performed whole-transcriptome RNA-sequencing (RNA-seq) of in vivo-selected, highly metastatic human breast cancer cell sub-lines, CN-LM1A and MDA-LM2, as well as the CN34 and MDA-MB-231 parental lines from which they were derived. To minimize the false positive rate and allow for subsequent statistical analysis, we sequenced biological replicates of each cell line. Mutations conferring enhanced metastatic capacity should be enriched in the transcriptomes of highly metastatic cells relative to their less metastatic parental populations.

Project description:Using criteria based on known examples, we identified approximately 1.7 million and 2.4 million sequences encoding putative miRNA precursor (stem-loop) structures in the mouse and human genomes, respectively, as well as large numbers of such structures in the genomes of fish, fruitfly and nematode worm. These predictions were then tested using high density custom microarrays containing modified oligonucleotides interrogated with purified small RNAs from different tissues. We found that 19% of 4,006 randomly chosen mouse predictions and 40% of 1,859 randomly chosen human predictions gave positive signals with small RNA isolated from whole 10-12 day embryos and a mixture of brain and testis, respectively, 84% of which hybridized to only one strand of the predicted stem-loop structure, whereas only 2% and 12% of equivalent random mouse and human predictions were positive. There was no difference in the validation rates between sequences exhibiting conservation and those that did not. High validation rates were also observed with predictions from fish, fly and worm genomes. Northern blot analysis of the array-positive mouse predictions confirmed that the vast majority of these sequences were detectable as small RNAs whose sizes ranged from 20-110 nucleotides. Taking into account false negative rates of the prediction and detection of known miRNAs, and assuming that this holds for other small RNAs, we estimate that there are 1 million small RNAs expressed in mouse and 3 million small RNAs in human. Keywords: genomic survey of small RNAs Stemloops were identified in the mouse and human genome using RNALfold with a window size of 110nt. Folding energy and other criteria were used to filter the structures into a set of miRNA-like stems. Stems were chosen randomly and probes designed against the stem regions. Stems were called present if one of the stem probes was more than 4 standard deviations above the signal distribution of mRNA degradation contamination probes designed against GAPDH and beta-actin.

Project description:Developmental exposure of mouse fetuses to estrogens results in dose-dependent permanent effects on prostate morphology and function. Fetal prostatic mesenchyme cells express estrogen receptor alpha (ERα) and androgen receptors and convert stimuli from estrogens and androgens into signaling to regulate epithelial cell proliferation and differentiation. To obtain mechanistic insight into the role of different doses of estradiol (E2) in regulating mesenchymal cells, we examined E2-induced transcriptomal changes in primary cultures of fetal mouse prostate mesenchymal cells. Urogenital sinus mesenchyme cells were obtained from male mouse fetuses at gestation day 17 and exposed to 10 pM, 100 pM or 100 nM E2 in the presence of a physiological concentration of dihydrotestosterone (0.69 nM) for four days. Gene ontology studies suggested that low doses of E2 (10 pM and 100 pM) induce genes involved in cell adhesion, morphological tissue development, and sterol biosynthesis but suppress genes involved in growth factor signaling and cell adhesion. Genes showing inverted-U-shape dose responses (enhanced by E2 at 10 pM E2 but suppressed at 100 pM) were identified, and their enrichment in the glycolytic pathway was demonstrated. At the highest dose (100 nM), E2 induced genes enriched not only for cell adhesion but also steroid hormone signaling and metabolism, cytokines and their receptors, cell-to-cell communication, Wnt signaling, and TGF-β signaling. These results suggest that prostate mesenchymal cells may regulate epithelial cells through direct cell contacts when estrogen level is low whereas soluble growth factors might play significant roles when estrogen level is high. Primary culture urogenital sinus mesenchymal cells were isolated from prostate glands of gestation day 17 CD1 male mouse fetuses. Cells were then exposed to 10 pM or 100 pM 17beta-estradiol or vehicle (0.05% ethanol) for four days in the presence of 690 pM 5alpha-dihydrotestosterone. Total cellular RNA was then isolated for determination of transcriptomal profiles by Affymetrix mouse gene 1.0 ST array.

Project description:Background Clinical success of T cell receptor (TCR) gene therapy has previously been demonstrated for NY-ESO-1 TCR gene therapy. To increase numbers of cancer patients that can be treated with TCR gene therapy we aimed to identify a novel set of high-affinity cancer specific TCRs targeting different cancer testis (CT) antigens in prevalent HLA class I alleles. Methods In this study, we selected based on publicly available gene expression databases the most promising CT genes to target. From these selected genes we identified by HLA peptidomics the naturally processed and presented HLA class I peptides. With these peptide-HLA tetramers were generated, and by single cell sorting CT specific CD8+ T cells were selected, and expanded from the allo-HLA repertoire of healthy donors. By several functional assays high avidity CT-specific T cell clones with safe recognition pattern were selected. To evaluate the potential for clinical application in TCR gene therapy, TCRs were sequenced and transferred into peripheral blood derived CD8+ T cells. Results In total we identified, 7 novel CT-specific TCRs that effectively target MAGE-A1, MAGE-A3, MAGE-A6 and MAGE-A9 in the context of human leukocyte antigen(HLA) -A1, -A2, -A3, -B7, -B35 and -C7. TCR gene transfer into CD8⁺ T cells resulted in efficient cytokine production and cytotoxicity of variety of different tumor types without detectable cross-reactivity. In addition, major in vivo antitumor effects of MAGE-A1 specific TCR engineered CD8⁺ T cells was observed in an orthotopic xenograft model for established multiple myeloma, in which bone marrow located tumor cells were completely eradicated after T cell injection. Conclusion The identification of 7 novel CT-specific TCRs, reactive against CT antigens presented in a variety of different HLA class I alleles, allows selection of therapeutic TCRs for an increased number of cancer patients, and will improve development of personalized TCR gene therapy.

Project description:MED1 (Mediator complex subunit 1) is expressed by human epidermal keratinocytes and functions as a coactivator of several transcription factors. To elucidate the role of MED1 in keratinocytes, we established keratinocyte-specific MED1-null (MED1epi-/-) mice using the K5Cre-LoxP system. To elucidate the mechanism(s) underlying abnormalities of keratinocytes derived from MED1epi-/- mice, we compared the gene expression patterns of MED1epi-/--derived keratinocytes with their wild type counterparts by microarray analysis. Generation of the MED1 conditional null mutation in epidermal keratinocytes and cell culture: MED1flox/flox mice (Jia et al, J Biol Chem 279:24427. 2004) were mated with K5Cre mice (Tarutani et al, Proc Natl Acad Sci U S A 94:7400. 1997) to generate F1 K5Cre+;MED1flox/+ mice. The K5Cre+;MED1flox/+ mice were then mated with MED1flox/flox mice to generate K5Cre+;MED1flox/flox mice (MED1epi-/-). Mice were screened for presence of the transgene by PCR using specific primers for the floxed MED1 gene and the human K5 gene according to the previous reports. Skin of newborn mice was excised after the mice were sacrificed with excessive anesthetic and were treated with dispase followed by trypsin to separate the epidermis from the dermis. Keratinocytes were seeded on type I collagen coated dishes, and were cultured in CnT07 conditioned culture medium (CELLnTEC, Bern, Switzerland). Keratinocytes were used for the experiment as a primary culture. All animal studies were conducted according to protocols approved by the Institutional Animal Care and Use Committee at Osaka University. Microarray analysis: For comprehensive comparison of gene expression patterns between keratinocytes derived from MED1epi-/- and from WT mice, microarray analysis was used. Total RNAs were extracted using an RNeasy kit (Qiagen, San Diego, CA). Then, 2μg total RNA was reverse transcribed to cDNA with T7 oligo d(T) primer (Affymetrix, Santa Clara, CA). The cDNA synthesis products were used for in vitro transcription reactions containing T7 RNA polymerase and biotinylated nucleotide analogue (pheudouridine base) cRNAs. The labeled cRNA products were then fragmented and loaded onto GeneChip(R) Mouse Genome 430 2.0 arrays (Affymetrix), and were hybridized according to the manufacturer’s protocol. Streptavidin-Phycoerythrin (Molecular Probes) was used as the fluorescent conjugate to detect hybridized target sequences. Raw intensity data from the GeneChip array were analyzed by GeneChip Operating Software (Affymetrix).

Dataset Information

Noncoding somatic and inherited single-nucleotide variants converge to promote ESR1 expression in breast cancer

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure