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-θ) regulates EMT by acting as a critical chromatin-anchored switch for inducible genes. Genome-wide transcriptome analysis identifies a unique cohort of inducible PKC-θ-sensitive genes in MCF7 cells stimulated with phorbol ester. MCF7 Cells treated with mock or siRNA against PKCtheta were left unstimulated or stimulated with PMA. 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. 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-θ) regulates EMT by acting as a critical chromatin-anchored switch for inducible genes. Genome-wide transcriptome analysis identifies a unique cohort of inducible PKC-θ-sensitive genes in MCF7 cells stimulated with phorbol ester.
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: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:The breast tumour microenvironment (TME) includes fibroblasts, adipocytes, inflammatory and immune cells. While treatment of tumours with chemotherapeutic agents such as Docetaxel, leads to apoptosis of tumour cells, it can also have consequences for the cellular makeup and transcriptional profile of the TME and these, like increased epithelial mesenchymal transition can promote undesirable consequences, such as Cancer Stem Cell development. PKC-theta may have a role in these undesired effects. To be able to examine the effects of co-treatment of Docetaxel with an inhibitor of PKC-theta, we performed RNA-seq on tumours from mice injected with the human breast cancer cell line MDA-MB-231. We then separated reads mapped to the human and mouse genomes in silico, creating tumour and TME transcriptomes for control, Docetaxel, PKC-theta inhibitor and combination treated mice. Separation of the tumour and TME profiles illustrated a role for PKC-theta in the induction of a more basal-type transcriptome in the tumour, and of EMT in the TME.
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: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:Adaptive immune responses to infection result in the formation of memory T and B cells that respond more rapidly and robustly to reinfections, providing the basis of the immunological memory targeted by vaccines. Underlying the enhanced responsiveness of memory cells is their ability to rapidly up-regulate the transcription of key effector genes at a higher level compared to naïve cells (termed transcriptional memory). While transcriptionally permissive histone modifications are known to provide chromatin structures that facilitate transcriptional memory, the molecular mechanisms that underpin this process still remain elusive. The role of the cytoplasmic signalling kinase, PKC-θ in T cell signalling cascades is well established, however PKC-θ has also recently been described as a chromatin-modifying enzyme. We have previously demonstrated that PKC-θ forms a part of an active transcription complex that docks at the IL2 gene - a gene which displays transcriptional memory. In this study, we perturbed PKC-θ expression using approaches such as siRNA knockdown in primary human naïve and memory CD4+ T cells to show that transcriptional memory is highly dependent on PKC-θ, particularly in memory CD4+ T cells. Chromatin-tethered PKC-θ was immuno-precipitated with high levels of the activating marks, H3K4me3 and H3K9ac and low levels of the repressive mark, H3K27me3 at the IL2 promoter in ex vivo-derived, activated memory CD4+ T cells. Further ChIP-sequencing analysis revealed that PKC-θ was prevalent at transcriptionally permissive domains such as promoters, upstream regions and exons but also at intronic regions containing putative enhancers annotated to a subset of genes preferentially expressed in memory CD4+ T cells. Collectively, these data argue that chromatin-tethered PKC-θ can directly regulate genes to establish and maintain a permissive chromatin state that facilitates transcriptional memory in human CD4+ T cells.
Project description:The present study is aimed at detecting and measuring mRNA levels of genes involved in epithelial to mesenchymal transition (EMT) in biological samples, i.e. in peripheral blood samples of colorectal cancer (CRC) patients and healthy controls, to determine the presence of disease, its progression and risk of recurrence.