Project description:TWIST1 is known to play a role in the metastatic progression of melanoma. However, the range of TWIST1 targets is poorly charachterized. Here microarray analysis was used to define the TWIST1 regulated transcriptome in the human melanoma cell line WM793.
Project description:Glioblastoma multiforme (GBM) is the most common and aggressive malignant brain tumor among adults, which is characterized by high invasion, migration and proliferation abilities. One important process that contributes to the invasiveness of GBM is the epithelial to mesenchymal transition (EMT). EMT is regulated by a set of defined transcription factors which tightly regulate this process, among them is the basic helix-loop-helix family member, TWIST1. Here we show that TWIST1 is methylated on lysine-33 at chromatin by SETD6, a methyltransferase with expression levels correlating with poor survival in GBM patients. RNA-seq analysis in U251 GBM cells suggested that both SETD6 and TWIST1 regulate cell adhesion and migration processes. We further show that TWIST1 methylation attenuates the expression of the long-non-coding RNA, LINC-PINT, thereby suppressing EMT in GBM. Mechanistically, TWIST1 methylation represses the transcription of LINC-PINT by increasing the occupancy of EZH2 and the catalysis of the repressive H3K27me3 mark at the LINC-PINT locus. Under un-methylated conditions, TWIST1 dissociates from the LINC-PINT locus, allowing the expression of LINC-PINT which leads to increased cell adhesion and decreased cell migration. Together, our findings unravel a new mechanistic dimension for selective expression of LINC-PINT mediated by TWIST1 methylation.
Project description:TWIST1, a basic helix-loop-helix transcription factor is essential for the development of cranial mesoderm and cranial neural crest-derived craniofacial structures. Our previous work showed that, in the absence of TWIST1, some cells within the cranial mesoderm adopt an abnormal epithelial configuration. Here, we show by transcriptome analysis that loss of TWIST1 in the cranial mesoderm is accompanied by a reduction in the expression of genes that are associated with cell-extracellular matrix interactions and the acquisition of mesenchymal characteristics. By comparing the transcriptional profiles of cranial mesoderm-specific Twist1 loss-of-function mutant and control mouse embryos, we identified a set of genes that are both TWIST1-dependent and predominantly expressed in the mesoderm. By ChIP-seq in a cell line model of a TWIST1-dependent mesenchymal state, we identified, among the downstream genes, three direct transcriptional targets of TWIST1: Ddr2, Pcolce and Tgfbi. Our findings show that the mesenchymal properties of the cranial mesoderm is likely to be regulated by a network of TWIST1 targets genes that influence the extracellular matrix and cell-matrix interactions, and collectively they are required for the morphogenesis of the craniofacial structures. Chromatin extracts were subject to chromatin immunoprecipitation with anti TWIST1 monoclonal antibody (ChIP-seq). Input chromatin, not subject to ChIP was used as the negative control. Two independent replicate experiments were performed. Purified, immunoprecipitated DNA was sequenced at Australian Genome Research facility.
Project description:In this study, merging in silico transcriptomic data and in situ TMA studies, we first highlighted the clinical significance and the value as prognostic factors of the embryonic TFs TWIST1 and TWIST2, thus linking their level of expression with the outcome of NB patients. Secondly, using NB cells knocked out for the TWIST1 protein, we studied the biological impact of TWIST1 in tumors xenografts. The expression of TWIST1 was associated with enhanced primary and secondary tumor growth capacity in immunocompromised mice. Furthermore, tumors expressing TWIST1 were portrayed by a more aggressive phenotype, characterized by the presence of spindle shaped cells and the destruction of the ECM collagen fibers. Finally, the transcriptional signature deregulated by TWIST1 was found to have a clinical significance in human primary tumors and resulted to be able to activate the TME in ortho-derived xenograft. This dataset reports analyses that studied the impact of knockout of the TWIST1 protein on the secretome of the neuroblastoma cell line mentioned above.
Project description:Twist1 variants including wildtype Twist1, a non-phosphorylatable mutant Twist1/S42A and a phospho-mimicking mutant Twist1/S42D were expressed in 4T1 cells in which the endogenous Twist1 was depleted. We wanted to use microarray analysis to evaluate those genes that are differentially regulated by Twist1 variants.
Project description:Purpose: Next-generation sequencing (NGS) has revolutionized systems-based analysis of cellular pathways. The goals of this study are to compare NGS-derived suture transcriptome profiling (RNA-seq) among wild type, Twist1+/- and Twist1+/- with suture regeneration surgery mice Methods: Suture mRNA profiles from one week after induction of seven-month-old wild type, Twist1+/- and Twist1+/- with suture regeneration surgery mice were generated by deep sequencing, in triplicate, using Illumina NextSeq500. Results: Using an optimized data analysis workflow, we mapped about 70 million sequence reads per sample to the mouse genome ( mm10) and identified 43,644 transcripts in the suture of wild type, Twist1+/- and Twist1+/- with suture regeneration surgery mice with Partek E/M workflow.
Project description:In this study, we aimed to characterize the stimulatory role of TWIST1 in breast cancer cell proliferation, EMT and metastasis, uncover the underlying molecular mechanism, and identify potential therapeutic targets for treating BLBC. RNA-Seq analysis were performed to identify differentially expressed genes influenced by TWIST1 overexpression in breast cancer cell MCF7. Pathway enrichment analysis and gene set enrichment analysis were performed to identify TWIST1-regulated signaling pathways, particually the cancer-associated pathways. ChIP-Seq analysis was further performed to identify TWIST1-associated genomic regions in MCF7-TWIST1 cells. The potential direct target genes of TWIST1 were identified by combined analysis of the gene expression profiling data and ChIP-Seq data.
Project description:TWIST1, a basic helix-loop-helix transcription factor is essential for the development of cranial mesoderm and cranial neural crest-derived craniofacial structures. Our previous work showed that, in the absence of TWIST1, some cells within the cranial mesoderm adopt an abnormal epithelial configuration. Here, we show by transcriptome analysis that loss of TWIST1 in the cranial mesoderm is accompanied by a reduction in the expression of genes that are associated with cell-extracellular matrix interactions and the acquisition of mesenchymal characteristics. By comparing the transcriptional profiles of cranial mesoderm-specific Twist1 loss-of-function mutant and control mouse embryos, we identified a set of genes that are both TWIST1-dependent and predominantly expressed in the mesoderm. By ChIP-seq in a cell line model of a TWIST1-dependent mesenchymal state, we identified, among the downstream genes, three direct transcriptional targets of TWIST1: Ddr2, Pcolce and Tgfbi. Our findings show that the mesenchymal properties of the cranial mesoderm is likely to be regulated by a network of TWIST1 targets genes that influence the extracellular matrix and cell-matrix interactions, and collectively they are required for the morphogenesis of the craniofacial structures.
Project description:Twist1 encodes a basic helix-loop-helix (bHLH) transcription factor and is a key regulator of craniofacial development. Mutations of TWIST1 gene in human are associated with Saethre-Chotzen syndrome (SCS), a developmental disorder characterized by facial and skull malformations, which are phenocopied by Twist1-null heterozygous mice. Mechanisms that dictate the tissue-specificity of Twist1 in regulating distinct transcriptional targets in different craniofacial cell types remain to be determined. Our work using mass-spectrometry and co-expression analysis in cell lines and embryonic head tissues has revealed that the most prevalent forms of TWIST1 were homodimers and heterodimers with E-proteins (TCF3,TCF4 and TCF12). RNA-seq analysis of embryoid bodies expressing tethered TWIST-E-protein dimers, and ChIP-seq profiling of TWIST1 genome-wide binding sites revealed mechanisms of TWIST1 functional regulation. This study highlighted the pleiotropic roles of TWIST1 dimers in development and revealed a potential molecular mechanism underpinning Twist1-related developmental defects of craniofacial tissues.
Project description:To understand TWIST1 function in early neural development, we analyzed genome-wide binding sites of TWIST1 in mouse embryonic stem cells (mESC) induced for neurogenic differentiation by chromatin immunoprecipitation, followed by high-throughput sequencing