Differentiation events contribute to cellular heterogeneity within tumors and influence disease progression and response to therapy. Here we dissect the mechanisms controlling intratumoral heterogeneity within basal-like breast cancers. We show that cancer cells can transition between a differentiation state related to that of normal luminal progenitors and a state closer to that of mature luminal cells, and that this occurs through asymmetric cell divisions. The Polycomb factor EZH2 and the Notch pathway act to increase the rates of symmetric divisions that produce progenitor-like cells, while the FOXA1 transcription factor promotes asymmetric divisions that reduce the numbers of such cells. Through functional screening, we identified a group of regulators that control cancer cell differentiation state and the relative proportions of tumor cell subpopulations. Our findings highlight the regulation of asymmetric cell divisions as a mechanism controlling intratumoral heterogeneity, and identify molecular pathways that control breast cancer cellular composition. Overall design: Expression profiles of HCC70 cells expressing shRNAs targeting regulatory factors that influence basal-like cancer cell population composition
Regulation of Cellular Heterogeneity and Rates of Symmetric and Asymmetric Divisions in Triple-Negative Breast Cancer.
Cell line, Subject
View SamplesDifferentiation events contribute to cellular heterogeneity within tumors and influence disease progression and response to therapy. Here we dissect the mechanisms controlling intratumoral heterogeneity within basal-like breast cancers. We show that cancer cells can transition between a differentiation state related to that of normal luminal progenitors and a state closer to that of mature luminal cells, and that this occurs through asymmetric cell divisions. The Polycomb factor EZH2 and the Notch pathway act to increase the rates of symmetric divisions that produce progenitor-like cells, while the FOXA1 transcription factor promotes asymmetric divisions that reduce the numbers of such cells. Through functional screening, we identified a group of regulators that control cancer cell differentiation state and the relative proportions of tumor cell subpopulations. Our findings highlight the regulation of asymmetric cell divisions as a mechanism controlling intratumoral heterogeneity, and identify molecular pathways that control breast cancer cellular composition. Overall design: Expression profiles of three cell subpopulations – K18+, K18+K14+ and K18+Vim+ – sorted from the breast cancer cell lines HCC70 and MDA-MB-468
Regulation of Cellular Heterogeneity and Rates of Symmetric and Asymmetric Divisions in Triple-Negative Breast Cancer.
Cell line, Subject
View SamplesXBP1 is the transcriptino factor that is activated by the ER stress. XBP1 is known to induce the ER dexpansion and increase the expression of the ER chaperone genes to prtect the cell from the ER stress. We generated a mouse strain that lacked XBP1 specifically in the mouse intestine by breeding the XBP1flox mice with Villin-cre mice. Here we examined genes that are differentially expressed between WT and XBP1 KO mouse intestine to identify genes that are downstream of XBP1.
XBP1 links ER stress to intestinal inflammation and confers genetic risk for human inflammatory bowel disease.
No sample metadata fields
View SamplesTo examine the effect of seminal fluid on the whole genome expression profile of endometrial tissue following mating, RNA was extracted from endometrial tissue collected 8 h after CBAF1 females were mated with intact Balb/c males and compared to RNA from endometrial tissue of females mated with seminal fluid deficient SVX/VAS Balb/c males. This comparison controlled for ovarian hormone status, exposure to the male and mating activity, and the neuroendocrine response to cervical and vaginal stimulus at mating, so that changes in endometrial gene expression could be attributed specifically to contact with seminal fluid. The endometrial RNA from n=16 individual females was pooled into four independent biological replicates per treatment group (n=4 endometrial samples per replicate) and expression profiles were analyzed by Affymetrix microarray. Seminal fluid exposure induced a clear difference in the profile of genes expressed in the endometrium with a total of 335 genes were differentially regulated with a fold-change greater than 1.5 and p<0.05. Of these, 190 genes were upregulated and 145 genes were downregulated following contact with seminal fluid. Bioinformatics analysis revealed TLR4 signaling as a strongly predicted upstream regulator activated by the differentially expressed genes.Additional experiments confirmed the role of TLR4 with the absence of TLR4 in TLR4 null mice resulting in a failure for seminal fluid to induce endometrial Csf3, Cxcl2, Il6 and Tnf expression. This study provides evidence that TLR4 contributes to seminal fluid modulation of the periconception immune environment. Activation of TLR4 signaling by microbial or endogenous components of seminal fluid is thus implicated as a key element of the female tract response to seminal fluid at the outset of pregnancy in mice.
TLR4 Signaling Is a Major Mediator of the Female Tract Response to Seminal Fluid in Mice.
Sex, Specimen part, Time
View SamplesNeuronal function critically depends on coordinated subcellular distribution of mRNAs. Disturbed mRNA processing and axonal transport has been found in spinal muscular atrophy and could be causative for dysfunction and degeneration of motoneurons. Despite the advances made in characterizing the transport mechanisms of several axonal mRNAs, an unbiased approach to identify the axonal repertoire of mRNAs in healthy and degenerating motoneurons has been lacking. Here we used compartmentalized microfluidic chambers to investigate the somatodendritic and axonal mRNA content of cultured motoneurons by microarray analysis. In axons, transcripts related to protein synthesis and energy production were enriched relative to the somatodendritic compartment. Knockdown of Smn, the protein deficient in spinal muscular atrophy, produced a large number of transcript alterations in both compartments. Transcripts related to immune functions, including MHC class I genes, and with roles in RNA splicing were upregulated in the somatodendritic compartment. On the axonal side, transcripts associated with axon growth and synaptic activity were downregulated. These alterations provide evidence that subcellular localization of transcripts with axonal functions as well as regulation of specific transcripts with nonautonomous functions is disturbed in Smn-deficient motoneurons, most likely contributing to the pathophysiology of spinal muscular atrophy.
Subcellular transcriptome alterations in a cell culture model of spinal muscular atrophy point to widespread defects in axonal growth and presynaptic differentiation.
Specimen part
View SamplesThe growth of the mammalian ovarian follicle requires the formation of a fluid filled antrum, and maturation and differentiation of the ovarian granulosa cells, largely under the control of Follicle Stimulating Hormone (FSH). Many follicles will regress and die by a process called atresia at this early antral stage. We therefore decided to analyse the gene expression profiles of granulosa cells cultured in the presence or absence of FSH and Tumour Necrosis Factor-alpha (TNF), an apoptotic factor, to simulate the key influences. Different concentratons of FSH and TNFa in granulosa culture were used to determine effective conditions via estradiol and progesterone production, and cell number.
The global effect of follicle-stimulating hormone and tumour necrosis factor α on gene expression in cultured bovine ovarian granulosa cells.
Specimen part, Treatment
View SamplesCell based bone regeneration strategies offer promise for traumatic bone injuries, congenital defects, non-union fractures and other skeletal pathologies. Postnatal bone remodeling and fracture healing provide evidence that an osteochondroprogenitor cell is present in adult life which can differentiate to remodel or repair the fractured bone. However, cell based skeletal repair in the clinic is still in its infancy mostly due to poor characterization of progenitor cells and lack of knowledge about their in vivo behavior. Here we took a combined approach of high throughput screening, flow based cell sorting and in vivo transplantation to identify markers that identify osteochondroprogenitor cells. We show that the presence of tetraspanin CD9 enriches for osteochondroprogenitors within CD105+vemesenchymal cells and these cells readily form bone upon transplantation. In addition we have used Thy1.2 (CD90) and the ectonucleotidase CD73 to identify subsets within the CD9+ve population that lead to endochondral or intramembranous-like bone formation. Utilization of this unique cell surface phenotype to enrich for osteochondroprogenitor cells will allow for further characterization of the molecular mechanisms that regulate their osteogenic properties.
Tetraspanin CD9 and ectonucleotidase CD73 identify an osteochondroprogenitor population with elevated osteogenic properties.
No sample metadata fields
View SamplesmRNA sequencing analysis of FACS-purified leptotene/zygotene (L/Z) spermatocytes Overall design: Compare transcriptomes of WT, Pld6 KO, and Dnmt3l KO germ cells in the F1 hybrid background of B6 and MSM to study these mutations affecting gene expression due to nearby retrotransposons.
Switching of dominant retrotransposon silencing strategies from posttranscriptional to transcriptional mechanisms during male germ-cell development in mice.
Cell line, Subject
View SamplesTo investigate the role of p53 and DICER in the induction of ER stress, wildtype, p53 knockout or DICER mutant HCT116 colon cancer cells were treated with the ER stress inducers tunicamycin or brefeldin A for 24 hours.
A close connection between the PERK and IRE arms of the UPR and the transcriptional regulation of autophagy.
Cell line, Treatment
View SamplesAnalysis of gene expression changes in the LV of a rodent heart that occur with uncontrolled diabetes
Transcriptomic analysis of the cardiac left ventricle in a rodent model of diabetic cardiomyopathy: molecular snapshot of a severe myocardial disease.
No sample metadata fields
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