CSL is a key transcription factor, mostly acting as a repressor. While known as main effector of Notch signaling, it can also play Notch-independent functions. Despite the wide interest in CSL, the mechanisms responsible for its own regulation have been little studied. We recently showed that CSL down-modulation in human dermal fibroblasts (HDFs) leads to conversion into cancer associated fibroblasts, which promote keratinocyte tumor development. We show here that levels of CSL gene transcription differ among HDF strains derived from many different individuals, with negative correlation with genes involved in DNA damage/repair. CSL expression in all tested strains is negatively regulated by stress / DNA damaging insults caused by UVA, Reactive Oxygen Species (ROS), smoke extract and doxorubicin treatment. p53, a key effector of the DNA damage response, functions as common negative regulator of CSL gene transcription, through both suppression of CSL promoter activity and, indirectly, through increased p21 expression. CSL was previously shown to bind p53 suppressing its activity. The present findings indicate that p53, in turn, decreases CSL expression, which can serve to enhance p53 activity in the acute response of cells to DNA damaging cancer-threatening conditions. Overall design: RNA sequencing of 46 human foreskin fibroblasts
Negative control of CSL gene transcription by stress/DNA damage response and p53.
No sample metadata fields
View SamplesSkin squamous cell carcinomas are among the most frequent human cancers. In this study we compared the expression profiles of 10 skin SCCs with a set of 3 normal human epidermis controls.
Multifactorial ERβ and NOTCH1 control of squamous differentiation and cancer.
Disease, Disease stage
View SamplesSenescence of stromal fibroblasts has been linked to establishment of cancer associated fibroblasts (CAF) and aging-associated increase of tumors. However, in clinically occurring carcinomas, density and proliferation of CAFs are frequently increased rather than decreased. We previously showed that genetic deletion or down-modulation of the canonical Notch effector CSL/RBP-J? in skin dermal fibroblasts is sufficient for CAF activation with consequent development of multifocal keratinocyte tumors. We now show that CSL deletion or knockdown induces senescence of primary fibroblasts derived from dermis, oral mucosa, breast and lung. CSL functions in these cells as a constitutive direct repressor of multiple senescence- and CAF-effector genes. At the same time, it physically interacts with p53, repressing its activity, and p53 activation provides a failsafe mechanism against compromised CSL function. Concomitant loss of CSL and p53 overcomes fibroblast senescence, enhances expression of CAF effector genes and, in vivo, promotes tumour and stromal cell expansion. Together, the findings support a CAF activation/stromal evolution model under convergent CSL/p53 control. Overall design: Human Dermal Fibroblasts were transfected with two different siRNA against CSL in parallel with a control siRNA. Total RNA was extracted 3 days post-transfection, followed by RNA-Seq analysis.
Combined CSL and p53 downregulation promotes cancer-associated fibroblast activation.
No sample metadata fields
View SamplesSenescence of stromal fibroblasts has been linked to establishment of cancer associated fibroblasts (CAF) and aging-associated increase of tumors. However, in clinically occurring carcinomas, density and proliferation of CAFs are frequently increased rather than decreased. We previously showed that genetic deletion or down-modulation of the canonical Notch effector CSL/RBP-J-kappa in skin dermal fibroblasts is sufficient for CAF activation with consequent development of multifocal keratinocyte tumors. We now show that CSL deletion or knockdown induces senescence of primary fibroblasts derived from dermis, oral mucosa, breast and lung. CSL functions in these cells as a constitutive direct repressor of multiple senescence- and CAF-effector genes. At the same time, it physically interacts with p53, repressing its activity, with p53 activation providing a failsafe mechanism against compromised CSL function. Concomitant loss of CSL and p53 overcomes fibroblasts senescence, enhances CAF effector gene expression and, in vivo, promotes stromal and cancer cell expansion. Together, these findings support a CAF activation/stromal evolution model under convergent CSL/p53 control.
Combined CSL and p53 downregulation promotes cancer-associated fibroblast activation.
Specimen part
View SamplesCancer cells express different sets of receptor type tyrosine kinases. These receptor kinases may be activated through autocrine or paracrine mechanisms. Fibroblasts may modify the biologic properties of surrounding cancer cells through paracrine mechansms.
The role of HGF/MET and FGF/FGFR in fibroblast-derived growth stimulation and lapatinib-resistance of esophageal squamous cell carcinoma.
Specimen part, Cell line
View SamplesRNA expression microarray analysis of prospermatogonia in 15 day post-conceptus (dpc) fetuses, a stage when they are undergoing rapid de novo DNA methylation. For comparison, we also analysed 15 dpc pachytene oogonia, 15 dpc female and male gonadal somatic cells, and adult pachytene spermatocytes.
RNA expression microarray analysis in mouse prospermatogonia: identification of candidate epigenetic modifiers.
Sex, Specimen part
View SamplesSOX9 is a transcriptional activator required for chondrogenesis, and SOX5 and SOX6 are closely related DNA-binding proteins that critically enhance its function. We used RNA-seq to charatierize a rat chondrosarcoma (RCS) cells as a faithful model for proliferating/early prehypertrophic growth plate chondrocytes and ChIP-seq to gain novel insights into the full spectrum of the target genes and modes of action of this chondrogenic trio. Overall design: RNAs were isolated from three bioogical replicatse of rat chondrosarcoma (RCS) cells and rib samples for RNA-seq experiments.
The transcription factors SOX9 and SOX5/SOX6 cooperate genome-wide through super-enhancers to drive chondrogenesis.
No sample metadata fields
View SamplesThe hair of all mammals consists of terminally differentiated cells that undergo a specialized form of apoptosis called cornification. While DNA is destroyed during cornification, the extent to which RNA is lost is unknown. Here we find that multiple types of RNA are incompletely degraded after hair shaft formation in both mouse and human. Notably, mRNAs and short regulatory microRNAs (miRNAs) are stable in the hair as far as 10 cm from the scalp. To better characterize the post-apoptotic RNAs that escape degradation in the hair, we performed sequencing (RNA-seq) on RNA isolated from hair shafts pooled from several individuals. This hair shaft RNA library, which encompasses different hair types, genders, and populations, revealed 7,193 mRNAs, 449 miRNAs and thousands of unannotated transcripts that remain in the post-apoptotic hair. A comparison of the hair shaft RNA library to that of viable keratinocytes revealed surprisingly similar patterns of gene coverage and indicates that degradation of RNA is highly inefficient during apoptosis of hair lineages. The generation of a hair shaft RNA library could be used as months of accumulated transcriptional history useful for retrospective detection of disease, drug response and environmental exposure.
The post-apoptotic fate of RNAs identified through high-throughput sequencing of human hair.
No sample metadata fields
View SamplesCD74, a Type II membrane glycoprotein and MHC class II chaperone (Ii), is normally expressed by cells associated with the immune system. CD74 also forms heterodimers with CD44 to generate receptors to macrophage migration inhibitory factor (MIF), a proinflammatory cytokine. Following targeted Cre-mediated deletion of Ikk in IkkDeltaHep mice (a strain highly susceptible to chemically-induced hepatotoxicity and hepatocarcinogenesis), CD74 is abundantly expressed by hepatocytes throughout liver acini (as detected by specific Western blots and immunohistochemical stains); it is not observed in either control IkkF/F hepatocytes or embryonic fibroblasts from Ikk-/- mice. Constitutive CD74 expression in IkkDeltaHep hepatocytes is also accompanied by significantly augmented expression of CD44 and genes associated with antigen processing and host defense. These observations suggest that IkkDeltaHep hepatocytes might directly respond to MIF signaling, accounting partly for the enhanced susceptibility of IkkDeltaHep mice to hepatotoxins and hepatocarcinogens, and also might exhibit unusual immunological properties including antigen presentation.
Targeted deletion of hepatocyte Ikkbeta confers growth advantages.
Specimen part
View SamplesThe molecular processes underlying human milk production and the effects of mastitic infection are largely unknown because of limitations in obtaining tissue samples. Determination of gene expression in normal lactating women would be a significant step towards understanding why some women display poor lactation outcomes. Here we demonstrate the utility of RNA obtained directly from human milk cells to detect mammary epithelial cell (MEC)-specific gene expression. Milk cell RNA was collected from 5 time points (24 hours pre-partum during the colostrum period, mid lactation, two involution, and during a bout of mastitis) in addition to an involution series comprising three time points. Gene expression profiles were determined by use of human Affymetrix arrays. Milk cells collected during milk production showed that the most highly expressed genes were involved in milk synthesis (eg. CEL, OLAH, FOLR1, BTN1A1, ARG2), while milk cells collected during involution showed a significant down regulation of milk synthesis genes and activation of involution associated genes (eg. STAT3, NF-kB, IRF5, IRF7). Milk cells collected during mastitic infection revealed regulation of a unique set of genes specific to this disease state, whilst maintaining regulation of milk synthesis genes. Use of conventional epithelial cell markers was used to determine the population of MECs within each sample. This paper is the first to describe the milk cell transcriptome across the human lactation cycle and during mastitic infection, providing valuable insight into gene expression of the human mammary gland.
Analysis of human breast milk cells: gene expression profiles during pregnancy, lactation, involution, and mastitic infection.
Specimen part
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