Project description:Vicious circle of some key proteins is critical in the process of tumor development. Nevertheless, the mechanism of how the epigenetic modifiers are involved in was seldom reported and has not been clearly illustrated. We found the expression of lysine specific demethylase 1 (LSD1), the first identified histone lysine demethylase, is positively correlated with transforming growth factor beta 1 (TGF β1) in gastric cancer tissues and can be promoted by TGF β1 activated (p-EKR)-(NF-κB)-p300 signaling pathway, which resulted in the progression of epithelial-mesenchymal transition (EMT) in human gastric cancer cells. On the other hand, abrogation of LSD1 leads to the down regulation of TGF β1 as well as the EMT. But in benign cells, this circle was blocked by TGF β1 induced inactivation of ERK, which suggested the distinct roles of TGF β1 against LSD1 in gastric cancer cells and benign cells. This vicious cycle may illustrate a novel mechanism for EMT in gastric cancer mediate by TGF β1 and LSD1 but not in benign cells and may serve as a new strategy for the prevention of EMT for gastric cancer.
Project description:Vicious circle of some key proteins is critical in the process of tumor development. Nevertheless, the mechanism of how the epigenetic modifiers are involved in was seldom reported and has not been clearly illustrated. We found the expression of lysine specific demethylase 1 (LSD1), the first identified histone lysine demethylase, is positively correlated with transforming growth factor beta 1 (TGF β1) in gastric cancer tissues and can be promoted by TGF β1 activated (p-EKR)-(NF-κB)-p300 signaling pathway, which resulted in the progression of epithelial-mesenchymal transition (EMT) in human gastric cancer cells. On the other hand, abrogation of LSD1 leads to the down regulation of TGF β1 as well as the EMT. But in benign cells, this circle was blocked by TGF β1 induced inactivation of ERK, which suggested the distinct roles of TGF β1 against LSD1 in gastric cancer cells and benign cells. This vicious cycle may illustrate a novel mechanism for EMT in gastric cancer mediate by TGF β1 and LSD1 but not in benign cells and may serve as a new strategy for the prevention of EMT for gastric cancer. Nuclear extracts prepared from MGC803 cells stably expressing Lenti-CAS9-sgRNA-puro for LSD1 or empty vector were used in immunoprecipitation reactions with antibodies against H3K4me2 and H3K9me2. Sequencing libraries were prepared using the TruSeq DNA Sample Prep Kit (Illumina) and sequencing was performed on a HiSeq2000 (Illumina).
Project description:Epithelial-mesenchymal transition (EMT) has recently been recognized as a key element of cell invasion, migration, metastasis, and drug resistance in several types of cancer, including non-small cell lung cancer (NSCLC). Our aim was to clarify microRNA (miRNA) -related mechanisms underlying EMT followed by acquired resistance to epidermal growth factor receptor tyrosine-kinase inhibitor (EGFR-TKI) in NSCLC. MiRNA expression profiles were examined before and after transforming growth factor-beta1 (TGF-β1) exposure in four human adenocarcinoma cell lines with or without EMT. Correlation between expressions of EMT-related miRNAs and resistance to EGFR-TKI gefitinib was evaluated. MiRNA array and quantitative RT-PCR revealed that TGF-β1 significantly induced overexpression of miR-134, miR-487b, and miR-655, which belong to the same cluster located on chromosome 14q32, in lung adenocarcinoma cells with EMT. MAGI2 (membrane-associated guanylate kinase, WW and PDZ domain-containing protein 2), a predicted target of these miRNAs and a scaffold protein required for PTEN (phosphatase and tensin homolog), was diminished in A549 cells with EMT after the TGF-β1 stimulation. Overexpression of miR-134 and miR-487b promoted the EMT phenomenon and affected the drug resistance to gefitinib, whereas knockdown of these miRNAs inhibited the EMT process and reversed TGF-β1-induced resistance to gefitinib. Our study demonstrated that the miR-134/487b/655 cluster contributed to the TGF-β1-induced EMT phenomenon and affected the resistance to gefitinib by directly targeting MAGI2, whose suppression subsequently caused loss of PTEN stability in lung cancer cells. The miR-134/miR-487b/miR-655 cluster may be new therapeutic targets in advanced lung adenocarcinoma patients, depending on the EMT phenomenon.
Project description:PHF8 exerts distinct functions in different types of cancer. However, the mechanisms underlying its specific functions in each case remain obscure. To establish whether overexpression of PHF8 regulates the TGF-β induced the epithelial-mesenchymal transition (EMT), we treated MCF10A-Mock (control) and MCF10A-PHF8wt (overexpressing wild-type PHF8) cells with TGF-β1 for 0, 24, 48 and 72 hours and performed RNA-seq in biological duplicates. Our data indicated that EMT gene signatures were significantly enriched in MCF10A-PHF8 cells with TGF-β1 treatment at all time points, strongly indicating that PHF8 overexpression induces a sustained EMT signaling program.
Project description:To identify the dysregulated lncRNA and mRNA expression in ARPE-19 cells underwent EMT, we established a TGF-β1 induced EMT model of ARPE-19 cells. ARPE-19 cells were treated with or without 10 ng/ml TGF-β1 for 48 h. Total RNA are extracted and subjected to microarray assay (Arraystar Human LncRNA Microarray V3.0)
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.