Dual role of CSL (RBP-Jk) and NOTCH1 in cancer-associated fibroblast genome stability and expansion [RNA-seq]
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE113542 | GEO | 2019/09/11
REPOSITORIES: GEO
Similar Datasets
Project description:Cancer associated fibroblasts (CAFs) represent a key component of the tumor microenvironment. Possible genomic alterations in these cells remain a point of contention. The skin is constantly exposed to clastogenic insults, such as UVA light that can target directly the stromal compartment, therefore representing a relevant model to study. Here we report that CAFs from skin Squamous Cell Carcinoma (SCC) lesions display chromosomal alterations, with heterogeneous levels of NOTCH1 gene amplification that also occur, to a lesser extent, in dermal fibroblasts of apparently unaffected skin. The fraction of the latter cells harboring NOTCH1 gene amplification is expanded by chronic UVA exposure, which induces a DNA damage response (DDR) to which CAFs are resistant. The selective advantage conferred by NOTCH1 gene amplification and over-expression can be explained by NOTCH1 ability to block DDR-mediated growth arrest through competitive suppression of ATM-FOXO3a association and downstream signaling cascade. These findings are of translational significance as, in an orthotopic model of skin SCC, genetic or pharmacological inhibition of NOTCH1 activity suppresses cancer / stromal cells expansion. Thus, NOTCH1 amplification and increased expression contribute to CAFs evolution and are an attractive target for preventing cancer / stromal cell expansion.
2020-08-25 | GSE113577 | GEO
Project description:Cancer associated fibroblasts (CAFs) play an important role in initiating and promoting epithelial cancers. The specific chromatin modifications involved in CAF activation remain to be elucidated. CSL, a constitutive transcriptional repressor and mediator of canonical Notch signaling, functions as a direct negative regulator of CAF effector genes and suppresses cancer/stromal cell expansion. We find that ATF3, a key stress responsive transcriptional repressor up-regulated in the acute UVA response of skin fibroblasts, is down-modulated in stromal cells of premalignant skin SCC lesions similarly to CSL. Increased ATF3 expression counteracts the consequences of compromised CSL, binding to a large set of overlapping target genes. At low basal levels, ATF3 converges with CSL in negative control of CAF activation, binding to a very small number of genomic loci that encompass mostly non-coding RNAs and pseudogenes. Silencing of ATF3 results in chromatin modifications and Pol II recruitment to many loci to which ATF3 does not bind, which are similarly affected by CSL silencing. The observed changes are of functional significance, as Bet inhibitors, which unlink activated chromatin from the basic transcription apparatus, have opposite effects of ATF3 or CSL silencing on all tested CAF effector genes. They exert a similar impact on clinically-derived CAFs both in vitro and upon topical in vivo treatment. Thus, ATF3 converges with CSL in global chromatin control of CAF activation with their loss eliciting epigenetic changes amenable to cancer and stroma-focused intervention.
2017-06-30 | GSE81405 | GEO
Project description:Cancer associated fibroblasts (CAFs) play an important role in initiating and promoting epithelial cancers. The specific chromatin modifications involved in CAF activation remain to be elucidated. CSL, a constitutive transcriptional repressor and mediator of canonical Notch signaling, functions as a direct negative regulator of CAF effector genes and suppresses cancer/stromal cell expansion. We find that ATF3, a key stress responsive transcriptional repressor up-regulated in the acute UVA response of skin fibroblasts, is down-modulated in stromal cells of premalignant skin SCC lesions similarly to CSL. Increased ATF3 expression counteracts the consequences of compromised CSL, binding to a large set of overlapping target genes. At low basal levels, ATF3 converges with CSL in negative control of CAF activation, binding to a very small number of genomic loci that encompass mostly non-coding RNAs and pseudogenes. Silencing of ATF3 results in chromatin modifications and Pol II recruitment to many loci to which ATF3 does not bind, which are similarly affected by CSL silencing. The observed changes are of functional significance, as Bet inhibitors, which unlink activated chromatin from the basic transcription apparatus, have opposite effects of ATF3 or CSL silencing on all tested CAF effector genes. They exert a similar impact on clinically-derived CAFs both in vitro and upon topical in vivo treatment. Thus, ATF3 converges with CSL in global chromatin control of CAF activation with their loss eliciting epigenetic changes amenable to cancer and stroma-focused intervention.
2017-06-30 | GSE81404 | GEO
Project description:Cancer associated fibroblasts (CAFs) play an important role in initiating and promoting epithelial cancers. The specific chromatin modifications involved in CAF activation remain to be elucidated. CSL, a constitutive transcriptional repressor and mediator of canonical Notch signaling, functions as a direct negative regulator of CAF effector genes and suppresses cancer/stromal cell expansion. We find that ATF3, a key stress responsive transcriptional repressor up-regulated in the acute UVA response of skin fibroblasts, is down-modulated in stromal cells of premalignant skin SCC lesions similarly to CSL. Increased ATF3 expression counteracts the consequences of compromised CSL, binding to a large set of overlapping target genes. At low basal levels, ATF3 converges with CSL in negative control of CAF activation, binding to a very small number of genomic loci that encompass mostly non-coding RNAs and pseudogenes. Silencing of ATF3 results in chromatin modifications and Pol II recruitment to many loci to which ATF3 does not bind, which are similarly affected by CSL silencing. The observed changes are of functional significance, as Bet inhibitors, which unlink activated chromatin from the basic transcription apparatus, have opposite effects of ATF3 or CSL silencing on all tested CAF effector genes. They exert a similar impact on clinically-derived CAFs both in vitro and upon topical in vivo treatment. Thus, ATF3 converges with CSL in global chromatin control of CAF activation with their loss eliciting epigenetic changes amenable to cancer and stroma-focused intervention.
2017-06-30 | GSE81403 | GEO
Project description:The age-associated increase of cancer risk has been linked with stromal fibroblast senescence and early steps of Cancer Associated Fibroblast (CAF) activation. Surprisingly little is known about the role of androgen receptor (AR) signalling in this context. We show that AR expression is down-modulated in stromal fibroblasts underlying premalignant skin cancer lesions (actinic keratoses, AK) as well as in CAFs from the three major skin cancer types, squamous (SCC) and basal cell (BCC) carcinomas and melanomas. Decreased AR expression is linked to the concomitant down-modulation of CSL, key effector of canonical Notch signalling and global modulator of chromatin configuration, and it can be counteracted by treatment with BET inhibitors, which reverse CAF activation. Functionally, AR gene silencing in dermal fibroblasts results in p53-dependent senescence and induction of key CAF-effector genes, with AR physically converging with CSL in negative control of these genes. The findings are of functional significance as, in an orthotopic model of skin cancer, dermal fibroblasts with AR loss enhance significantly tumorigenicity of SCC and melanoma cells. As such, the findings establish AR as a novel potential target for stroma-focused cancer prevention and treatment.
2018-08-28 | GSE107319 | GEO
Project description:The age-associated increase of cancer risk has been linked with stromal fibroblast senescence and early steps of Cancer Associated Fibroblast (CAF) activation. Surprisingly little is known about the role of androgen receptor (AR) signalling in this context. We show that AR expression is down-modulated in stromal fibroblasts underlying premalignant skin cancer lesions (actinic keratoses, AK) as well as in CAFs from the three major skin cancer types, squamous (SCC) and basal cell (BCC) carcinomas and melanomas. Decreased AR expression is linked to the concomitant down-modulation of CSL, key effector of canonical Notch signalling and global modulator of chromatin configuration, and it can be counteracted by treatment with BET inhibitors, which reverse CAF activation. Functionally, AR gene silencing in dermal fibroblasts results in p53-dependent senescence and induction of key CAF-effector genes, with AR physically converging with CSL in negative control of these genes. The findings are of functional significance as, in an orthotopic model of skin cancer, dermal fibroblasts with AR loss enhance significantly tumorigenicity of SCC and melanoma cells. As such, the findings establish AR as a novel potential target for stroma-focused cancer prevention and treatment.
2018-08-28 | GSE107320 | GEO
Project description:Senescence 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. Examination of genome-wide CSL binding sites in primary human dermal fibroblasts usinf two different antibodies against CSL
2015-08-24 | E-GEOD-59942 | biostudies-arrayexpress
Project description:Senescence 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-Jκ 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. 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.
2015-08-24 | E-GEOD-65473 | biostudies-arrayexpress
Project description:Down-modulation or loss-of-function mutations of the Notch 1 and 2 genes are associated with development of squamous cell carcinoma (SCC), a very frequent and therapy-resilient malignancy in skin, head/neck (H/N), lung and other surface epithelia. In this context, surprisingly little is known on the role of CSL (RBP-Jk), key effector of canonical Notch signaling endowed with intrinsic transcription repressive function. CSL expression is decreased in upper epidermal layers and differentiating primary human keratinocytes (HKCs), while it is up-regulated in premalignant and malignant SCC lesions and SCC cell lines from skin, Head/Neck and lung. Increased CSL levels enhance proliferation and self-renewal potential of HKCs and SCC cells, while its silencing induces growth arrest and apoptosis. In vivo, SCC cells with increased CSL levels give rise to rapidly expanding tumors, while upon CSL silencing they form smaller and more differentiated tumors with enhanced inflammatory infiltrate. Global transcriptomic analysis of HKC and SCC cells plus/minus CSL silencing reveals major modulation of apoptotic, cell cycle and pro-inflammatory genes, with no significant association with Notch or keratinocyte differentiation gene signatures. KDM6B, a histone demethylase gene with highly context dependent functions, is a direct CSL negative target, with an inverse role of CSL in HKC and SCC self-renewal and tumorigenesis, with IL6 as a target of likely significance. CSL / KDM6B protein expression could be used as biomarkers of SCC development and novel indicators of cancer treatment.
2017-12-15 | GSE102761 | GEO
Project description:Down-modulation or loss-of-function mutations of the Notch 1 and 2 genes are associated with development of squamous cell carcinoma (SCC), a very frequent and therapy-resilient malignancy in skin, head/neck (H/N), lung and other surface epithelia. In this context, surprisingly little is known on the role of CSL (RBP-Jk), key effector of canonical Notch signaling endowed with intrinsic transcription repressive function. CSL expression is decreased in upper epidermal layers and differentiating primary human keratinocytes (HKCs), while it is up-regulated in premalignant and malignant SCC lesions and SCC cell lines from skin, Head/Neck and lung. Increased CSL levels enhance proliferation and self-renewal potential of HKCs and SCC cells, while its silencing induces growth arrest and apoptosis. In vivo, SCC cells with increased CSL levels give rise to rapidly expanding tumors, while upon CSL silencing they form smaller and more differentiated tumors with enhanced inflammatory infiltrate. Global transcriptomic analysis of HKC and SCC cells plus/minus CSL silencing reveals major modulation of apoptotic, cell cycle and pro-inflammatory genes, with no significant association with Notch or keratinocyte differentiation gene signatures. KDM6B, a histone demethylase gene with highly context dependent functions, is a direct CSL negative target, with an inverse role of CSL in HKC and SCC self-renewal and tumorigenesis, with IL6 as a target of likely significance. CSL / KDM6B protein expression could be used as biomarkers of SCC development and novel indicators of cancer treatment.
2017-12-15 | GSE102762 | GEO