Identification of enhancers in EMT and breast cancer stem cell formation
Ontology highlight
ABSTRACT: Epithelial-mesenchymal transition (EMT), the process whereby cells gain migratory and invasive properties characteristic of mesenchymal cells, plays a central role in embryogenesis and wound healing in a wide range of tissues. However, EMT has also been linked to the formation of cancer stem cells (CSCs). Many of the signaling pathways involved in EMT have also been implicated in CSC formation but the processes that contribute uniquely to CSC formation remain elusive. We have previously demonstrated that PKCθ activation is critical for EMT induction and concomitant CSC formation in the breast cancer luminal epithelial cell line, MCF7. To discover how PKC-induced alterations in the epigenome influence the EMT and CSC formation in MCF-7 cells and MDA-MB-231, we employed a combination of expression profiling and ChIP-sequencing of H3K4me1 and H3K27ac.
Project description:Epithelial-mesenchymal transition (EMT), the process whereby cells gain migratory and invasive properties characteristic of mesenchymal cells, plays a central role in embryogenesis and wound healing in a wide range of tissues. However, EMT has also been linked to the formation of cancer stem cells (CSCs). Many of the signaling pathways involved in EMT have also been implicated in CSC formation but the processes that contribute uniquely to CSC formation remain elusive. We have previously demonstrated that PKCθ activation is critical for EMT induction and concomitant CSC formation in the breast cancer luminal epithelial cell line, MCF7. To discover how PKC-induced alterations in the epigenome influence the EMT and CSC formation in MCF-7 cells, we employed a combination of expression profiling and Formaldehyde Assisted Regulatory Elements (FAIRE)-sequencing in order to reveal novel links between gene expression and DNA accessibility changes after PKCθ activation. We found that, during EMT, increases in accessibility generally occurred in regions away from transcription start sites, low in CpG, enriched with chromatin marks of enhancer elements and motifs for FOX, AP1, TEAD and AP2. Increases in FOX and AP-1 motif accessibility were associated with genes that exhibited increased expression in CSC, while increased AP-2 accessibility was associated with genes that had higher expression in non-CSCs. This study revealed novel regions of DNA accessibility induced by PKC that contribute to the understanding of how epigenomic plasticity of cells undergoing EMT leads to the activation of genes that drive the CSC program.
Project description:Epithelial-mesenchymal transition (EMT), the process whereby cells gain migratory and invasive properties characteristic of mesenchymal cells, plays a central role in embryogenesis and wound healing in a wide range of tissues. However, EMT has also been linked to the formation of cancer stem cells (CSCs). Many of the signaling pathways involved in EMT have also been implicated in CSC formation but the processes that contribute uniquely to CSC formation remain elusive. We have previously demonstrated that PKCθ activation is critical for EMT induction and concomitant CSC formation in the breast cancer luminal epithelial cell line, MCF7. To discover how PKC-induced alterations in the epigenome influence the EMT and CSC formation in MCF-7 cells and MDA-MB-231, we employed a combination of expression profiling and ChIP-sequencing of H3K4me1 and H3K27ac. 3 biological samples were analyzed with two different chromatin marks.
Project description:Epithelial-mesenchymal transition (EMT), the process whereby cells gain migratory and invasive properties characteristic of mesenchymal cells, plays a central role in embryogenesis and wound healing in a wide range of tissues. However, EMT has also been linked to the formation of cancer stem cells (CSCs). Many of the signaling pathways involved in EMT have also been implicated in CSC formation but the processes that contribute uniquely to CSC formation remain elusive. We have previously demonstrated that PKCθ activation is critical for EMT induction and concomitant CSC formation in the breast cancer luminal epithelial cell line, MCF7. To discover how PKC-induced alterations in the epigenome influence the EMT and CSC formation in MCF-7 cells, we employed a combination of expression profiling and Formaldehyde Assisted Regulatory Elements (FAIRE)-sequencing in order to reveal novel links between gene expression and DNA accessibility changes after PKCθ activation. We found that, during EMT, increases in accessibility generally occurred in regions away from transcription start sites, low in CpG, enriched with chromatin marks of enhancer elements and motifs for FOX, AP1, TEAD and AP2. Increases in FOX and AP-1 motif accessibility were associated with genes that exhibited increased expression in CSC, while increased AP-2 accessibility was associated with genes that had higher expression in non-CSCs. This study revealed novel regions of DNA accessibility induced by PKC that contribute to the understanding of how epigenomic plasticity of cells undergoing EMT leads to the activation of genes that drive the CSC program. 2 biological samples were analysed with 2 biological replicates each and a mixed total input.
Project description:Epithelial to mesenchymal transition (EMT) is activated during cancer invasion and metastasis, enriches for cancer stem cells (CSCs), and contributes to therapeutic resistance and disease recurrence. The epithelial cell line MCF7, can be induced to undergo EMT with the induction of PKC by PMA. 5-10% of the resulting cells have a CSC phenotype. This study looks at the transcriptome of these cells and how it differs from cells with a non-CSC phenotype. Epithelial to mesenchymal transition (EMT) is activated during cancer invasion and metastasis, enriches for cancer stem cells (CSCs), and contributes to therapeutic resistance and disease recurrence. The epithelial cell line MCF7, can be induced to undergo EMT with the induction of PKC by PMA. 5-10% of the resulting cells have a CSC phenotype. This study looks at the transcriptome of these cells and how it differs from cells with a non-CSC phenotype. MCF7 cells were stimulated with PMA and FACS sorted. 4 samples, no replicates
Project description:Epithelial to mesenchymal transition (EMT) is activated during cancer invasion and metastasis, enriches for cancer stem cells (CSCs), and contributes to therapeutic resistance and disease recurrence. The epithelial cell line MCF7, can be induced to undergo EMT with the induction of PKC by PMA. 5-10% of the resulting cells have a CSC phenotype. This study looks at the transcriptome of these cells and how it differs from cells with a non-CSC phenotype. Epithelial to mesenchymal transition (EMT) is activated during cancer invasion and metastasis, enriches for cancer stem cells (CSCs), and contributes to therapeutic resistance and disease recurrence. The epithelial cell line MCF7, can be induced to undergo EMT with the induction of PKC by PMA. 5-10% of the resulting cells have a CSC phenotype. This study looks at the transcriptome of these cells and how it differs from cells with a non-CSC phenotype.
Project description:Epithelial to mesenchymal transition (EMT) is activated during cancer invasion and metastasis, enriches for cancer stem cells (CSCs), and contributes to therapeutic resistance and disease recurrence. Signal transduction kinases play a pivotal role as chromatin-anchored proteins in eukaryotes. Here we report for the first time that protein kinase C-theta (PKC-q) regulates EMT by acting as a critical chromatin-anchored switch for inducible genes via TGF-M-NM-2 and the key inflammatory regulatory protein, NFkB. Chromatinized PKC-q exists as an active transcription complex and is required to establish a permissive chromatin state at signature EMT genes. Genome-wide analysis identifies a unique cohort of inducible PKC-q-sensitive genes that are directly tethered to PKC-q in the mesenchymal state. Collectively, we show that crosstalk between signaling kinases and chromatin is critical for eliciting inducible transcriptional programs that drive mesenchymal differentiation and CSC formation, providing novel mechanisms to target using epigenetic therapy in breast cancer. 2 biological samples were analysed, Immunoprecipitated and total input samples were obtained from each biological treatment. 2 Technical replicates were performed (samples from the sample lib prep were run on two different lanes).
Project description:Complex regulatory networks control epithelial-to-mesenchymal transition (EMT) but the underlying epigenetic control is poorly understood. Lysine-specific demethylase 1 (LSD1) is a key histone demethylase that alters the epigenetic landscape. Here we explored the role of LSD1 in global epigenetic regulation of EMT, cancer stem cells (CSCs), the tumour microenvironment, and therapeutic resistance in breast cancer. LSD1 induced pan-genomic gene expression in networks implicated in EMT and selectively elicits gene expression programs in CSCs whilst repressing non-CSC programs. LSD1 phosphorylation at serine-111 (LSD1-s111p) by chromatin anchored protein kinase C-theta (PKC-θ), is critical for its demethylase and EMT promoting activity and LSD1-s111p is enriched in chemoresistant cells in vivo. LSD1 couples to PKC-θ on the mesenchymal gene epigenetic template promotes LSD1-mediated gene induction. In vivo, chemotherapy reduced tumour volume, and when combined with an LSD1 inhibitor, abrogated the mesenchymal signature and promoted an innate, M1 macrophage-like tumouricidal immune response. Circulating tumour cells (CTCs) from metastatic breast cancer (MBC) patients were enriched with LSD1 and pharmacological blockade of LSD1 suppressed the mesenchymal and stem-like signature in these patient-derived CTCs. Overall, LSD1 inhibition may serve as a promising epigenetic adjuvant therapy to subvert its pleiotropic roles in breast cancer progression and treatment resistance.
Project description:Epithelial to mesenchymal transition (EMT) is activated during cancer invasion and metastasis, enriches for cancer stem cells (CSCs), and contributes to therapeutic resistance and disease recurrence. Signal transduction kinases play a pivotal role as chromatin-anchored proteins in eukaryotes. Here we report for the first time that protein kinase C-theta (PKC-q) regulates EMT by acting as a critical chromatin-anchored switch for inducible genes via TGF-β and the key inflammatory regulatory protein, NFkB. Chromatinized PKC-q exists as an active transcription complex and is required to establish a permissive chromatin state at signature EMT genes. Genome-wide analysis identifies a unique cohort of inducible PKC-q-sensitive genes that are directly tethered to PKC-q in the mesenchymal state. Collectively, we show that crosstalk between signaling kinases and chromatin is critical for eliciting inducible transcriptional programs that drive mesenchymal differentiation and CSC formation, providing novel mechanisms to target using epigenetic therapy in breast cancer.
Project description:Epithelial-mesenchymal transition (EMT)/mesenchymal-epithelial transition (MET) processes are proposed to be a driving force of cancer metastasis. By studying metastasis in bone marrow-derived mesenchymal stem cell (BM-MSC)-driven lung cancer models, microarray time-series data analysis by systems biology approaches revealed BM-MSC-induced signaling triggers early dissemination of CD133+/CD83+ cancer stem cells (CSCs) from primary sites shortly after STAT3 activation but promotes proliferation towards secondary sites. The switch from migration to proliferation was regulated by BM-MSC-secreted LIF and activated LIFR/p-ERK/pS727-STAT3 signaling to promote early disseminated cancer cells MET and premetastatic niche formation. Then, tumor-tropic BM-MSCs circulated to primary sites and triggered CD151+/CD38+ cells acquiring EMT-associated CSC properties through IL6R/pY705-STAT3 signaling to promote tumor initiation and were also attracted by and migrated towards the premetastatic niche. In summary, STAT3 phosphorylation at tyrosine 705 and serine 727 differentially regulates the EMT-MET switch within the distinct molecular subtypes of CSCs to complete the metastatic process.
Project description:Cancer stem cells (CSCs) drive tumour spread and therapeutic resistance, and can undergo epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) to switch between epithelial and post-EMT sub-populations. Examining oral squamous cell carcinoma (OSCC), we now show that increased phenotypic plasticity, the ability to undergo EMT/MET, underlies increased CSC therapeutic resistance within both the epithelial and post-EMT sub-populations. The post-EMT CSCs that possess plasticity exhibit particularly enhanced therapeutic resistance and are defined by a CD44highEpCAMlow/-CD24+ cell surface marker profile. Treatment with TGFβ and retinoic acid (RA) enabled enrichment of this sub-population for therapeutic testing, through which the endoplasmic reticulum (ER) stressor and autophagy inhibitor Thapsigargin was shown to selectively target these cells. Demonstration of the link between phenotypic plasticity and therapeutic resistance, and development of an in vitro method for enrichment of a highly resistant CSC sub-population, provides an opportunity for the development of improved chemotherapeutic agents that can eliminate CSCs. The CA1 OSCC cell line was sub-cloned to derive 4 clonal sub-lines, termed pEMT-P, pEMT-S, Epi-S and Epi-P (here 18, 23, 7 and 4 respectively).