Transcriptome analysis of 12 zebrafish tissues
Gene evolution and gene expression after whole genome duplication in fish: the PhyloFish database.
No sample metadata fields
View SamplesTo examine whether the BPA-induced morphological alterations of the fetal mouse mammary glands are a) associated with changes in mRNA expression reflecting estrogenic actions and/or b) dependent on the estrogen receptor (ER), we compared the transcriptomal effects of BPA and the steroidal estrogen ethinylestradiol (EE2) on fetal mammary tissues of wild type and ER knock-out mice.
Low-dose BPA exposure alters the mesenchymal and epithelial transcriptomes of the mouse fetal mammary gland.
Sex, Specimen part
View SamplesEffects of betalains in C. elegans gene expression is studied, as our previous results showed a lifespan extension effect produced by theses molecules
Betalain health-promoting effects after ingestion in Caenorhabditis elegans are mediated by DAF-16/FOXO and SKN-1/Nrf2 transcription factors.
Age, Specimen part, Treatment
View SamplesCellular senescence is a program of irreversible cell cycle arrest that normal cells undergo in response to progressive shortening of telomeres, changes in telomeric structure, oncogene activation or oxidative stress. The underlying signalling pathways, potentially of major clinicopathological relevance, are unknown. A major stumbling block to studying senescence has been the absence of suitable model systems because of the asynchrony of this process in heterogeneous cell populations. To simplify this process many investigators study oncogene-induced senescence due to expression of activated oncogenes where senescence occurs prematurely without telomere attrition and can be induced acutely in a variety of cell types. We have taken a different approach by making use of the finding that reconstitution of telomerase activity by introduction of the catalytic subunit of human telomerase alone is incapable of immortalising all human somatic cells, but inactivation of the p16-pRB and p53-p21 pathways are required in addition. The ability of SV40 large T antigen to inactivate the p16-pRB and p53-p21 pathways has enabled us to use a thermolabile mutant of LT antigen, in conjunction with hTERT, to develop conditionally immortalised human (HMF3A) fibroblasts that are immortal but undergo an irreversible growth arrest when the thermolabile LT antigen is inactivated leading to activation of pRB and p53. When these cells cease dividing, senescence-associated- b-galactosidase activity is induced and the growth-arrested cells have morphological features and express genes in common with senescent cells. Since these cells growth arrest in a synchronous manner they are an excellent starting point for dissecting the pathways that underlie cellular senescence and act downstream of p16-pRB and p53-p21 pathways. We have combined genome-wide expression profiling with genetic complementation to undertake identification of genes that are differentially expressed when these conditionally immortalised human fibroblasts undergo senescence upon activation of the p16-pRB and p53-p21 tumour suppressor pathways.
Activation of nuclear factor-kappa B signalling promotes cellular senescence.
Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A stemness-related ZEB1-MSRB3 axis governs cellular pliancy and breast cancer genome stability.
Specimen part, Cell line
View SamplesAberrant cell proliferation, a hallmark of most cancers, requires the escape from intrinsic antitumour barriers. Primary among these is the DNA damage response (DDR). In both cell culture-models and in early stages of tumorigenesis in vivo, activated oncogenes induce DNA replication stress and DNA double-strand breaks (DSBs), leading to DDR activation and p53-dependent apoptosis and/or senescence. The means by which tumour-initiating cells, also termed cancer stem cells (CSCs), circumvent this oncosuppressive response is unknown. Here we demonstrate that the ZEB1 transcription factor provides breast CSCs with the ability to withstand an aberrant mitogenic activity. Its forced expression in human mammary epithelial cells is sufficient to alleviate DNA replicative stress and to decrease the production of reactive oxygen species, an important contributor to DDR and oncogene-induced senescence. Consistently, human breast cancer cells with endogenous ZEB1 expression show two characteristic features: low levels of DSBs and DDR markers, reflecting mitigation of the DNA replication stress, and a low p53 mutation frequency, reflecting a weak selective pressure for inactivation. Using high-throughput sequencing analysis of controlled cellular models, we further demonstrate that ZEB1 delays the onset of structural chromosomal instability (CIN), a known consequence of replicative stress and prevents the emergence of chromosome 8p deletions and 8q amplifications, two prevalent abnormalities in high-grade breast cancers. Supporting these findings, ZEB1 expression discriminates human breast tumours by their copy number alterations (CNAs) and chromosome 8 aberrations. We propose that the tumorigenic potential of CSCs relies upon their unique capacity to tolerate oncogenic stimuli through the alleviation of DNA replication stress.
A stemness-related ZEB1-MSRB3 axis governs cellular pliancy and breast cancer genome stability.
Specimen part
View SamplesBackground There are conflicting reports on the impact of soy on breast carcinogenesis. This study examines the effects of soy supplementation on breast cancer-related genes and pathways. Methods Women (n = 140) with early-stage breast cancer were randomized to soy protein supplementation (n = 70) or placebo (n = 70) for 7 to 30 days, from diagnosis until surgery. Adherence was determined by plasma isoflavones: genistein and daidzein. Gene expression changes were evaluated by NanoString inin pre- and post-treatment tumor tissue. Genome-wide expression analysis was performed on post-treatment tissue. Proliferation (Ki67) and apoptosis (Cas3) were assessed by immunohistochemistry. Results Plasma isoflavones rose in the soy group (two-sided Wilcoxon rank-sum test, P < .001) and did not change in the placebo group. In paired analysis of pre- and post-treatment samples, 21 genes (out of 202) showed altered expression (two-sided Students t-test, P < .05). Several genes including FANCC and UGT2A1 revealed different magnitude and direction of expression changes between the two groups (two-sided Students t-test, P < .05). A high-genistein signature consisting of 126 differentially expressed genes was identified from microarray analysis of tumors. This signature was characterized by overexpression (>2 fold) of cell cycle transcripts, including those which promote cell proliferation, such as FGFR2, E2F5, BUB1, CCNB2, MYBL2, CDK1, and CDC20 (P < .01). Soy intake did not result in statistically significant changes in Ki67 or Cas3. Conclusions Gene expression associated with soy intake and high plasma genistein define a signature characterized by overexpression of FGFR2 and genes that drive cell cycle and proliferation pathways. These findings raise the concerns that in a subset of women soy could adversely affect gene expression in breast cancer.
The effects of soy supplementation on gene expression in breast cancer: a randomized placebo-controlled study.
Treatment
View SamplesMatriptase-2 (Tmprss6), a recently described member of the TTSP family, is an essential regulator of iron homeostasis. Tmprss6-/- mice display an overt phenotype of alopecia and a severe iron deficiency anemia. These hematological alterations found in Tmprss6-/- mice are accompanied by a marked up-regulation of hepcidin, a negative regulator of iron export into plasma.
Membrane-bound serine protease matriptase-2 (Tmprss6) is an essential regulator of iron homeostasis.
Sex, Age, Specimen part
View SamplesThe in vitro directed differentiation of pluripotent stem cells (PSCs) through stimulation of developmental signaling pathways can generate mature somatic cell types for basic laboratory studies or regenerative therapies.
Pluripotent stem cell differentiation reveals distinct developmental pathways regulating lung- versus thyroid-lineage specification.
Treatment
View SamplesDiffuse large B-cell lymphoma (DLBCL) has striking clinical and molecular variability. Although a more precise identification of the multiple determinants of this variability is still under investigation, there is a consensus that high-clinical-risk DLBCL cases require a risk-adapted therapy, since intensification of chemotherapy with autologous stem-cell transplantation (ASCT) has been shown to improve the prognosis for high-risk patients in randomised clinical trials.
Identification of biological markers of sensitivity to high-clinical-risk-adapted therapy for patients with diffuse large B-cell lymphoma.
No sample metadata fields
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