Epigenomic Analyses Identify FOXM1 As a Key Regulator of Anti-Tumor Immune Response in Esophageal Adenocarcinoma
Ontology highlight
ABSTRACT: We identified FOXM1 as an EAC-specific candidate transcription factor using GSEA analysis. Functionality of FOXM1 was evaluated in both EAC patient derived organoids and EAC cell lines by measuring cell proliferation, colony formation, and xenograft growth. A FOXM1 signature through the overlap of ESO26, SKGT4, and OE33 intersected ChIP-seq peaks and ESO26 siFOXM1 RNA-seq downregulated genes. Upstream transcriptional regulation of FOXM1 was evaluated with this FOXM1 gene signature and validated using pharmacological inhibition. GSEA analysis determined that immune related pathways were upregulated in ESO26 cell lines treated with siFOXM1 or in TCGA EAC patients with low FOXM1 expression. Syngeneic xenografts found increases in CD8+ T cell infiltration in FOXM1 knockdown tumors. Loss of FOXM1 led to increased secretion of CD8+ T cell Th1 chemokines which play a role in the migration of CD8+ T cells upon loss of FOXM1. Finally, the loss of FOXM1 also increased Ex-vivo cytotoxic killing of murine cancer cells.
Project description:We profiled esophageal adenocarcinoma cell lines with chromatin immunoprecipitation sequencing (ChIP-Seq). Mathematically modeling was performed to establish (super)-enhancers landscapes and inter-connected transcriptional circuitry formed by master TFs. Coregulation and cooperation between master TFs was investigated by ChIP-Seq, RNA-Seq, 4C-Seq and luciferase assay. Biological functions of candidate factors were evaluated by measuring cell proliferation, colony formation, cell apoptosis and xenograft growth. Next-generation sequencing (NGS) has revolutionized systems-based analysis of cellular pathways. Here, we aim to compare of Eso26 or OE33 cells knock down PPARG with siRNA and control transcriptome profiling (RNA-seq) to microarray and quantitative reverse transcription polymerase chain reaction (qRT–PCR) methods and to evaluate protocols for optimal high-throughput data analysis. We also report the application of ChIP sequencing technology for studying master transcription factor (PPARG) in human esophageal adenocarcinoma cancer cell lines (Eso26 and OE33).
Project description:A nonsense mutation in ARID1A was identified by next generation sequencing in non-dysplastic Barrett's esophagus [BE] tissue and esophageal adenocarcinoma [EAC] tissue of a patient diagnosed with EAC. Immunohistochemistry performed on an independent archival cohort demonstrated ARID1A protein loss in 0% (0/76), 4.9% (2/40), 14.3% (4/28), 16.0% (8/50), and 12.2% (12/98) of normal squamous epithelium, BE, low-, high-grade dysplasia, and EAC tissues, respectively. Enhanced cell growth, proliferation and invasion were observed upon ARID1A knockdown in EAC cells. ARID1A was knocked down in OE33 cells (Sample MS_1 and MS_3) using on-TARGET smartpool ARID1A siRNA. At the same time, OE33 cells were transfected with a non-targeting siRNA, and these experiments (Samples MS_2 and MS_4) functioned as mock controls. Cells were harvested after 48 hours and total RNA was extracted using the Rneasy kit (Qiagen)
Project description:A nonsense mutation in ARID1A was identified by next generation sequencing in non-dysplastic Barrett's esophagus [BE] tissue and esophageal adenocarcinoma [EAC] tissue of a patient diagnosed with EAC. Immunohistochemistry performed on an independent archival cohort demonstrated ARID1A protein loss in 0% (0/76), 4.9% (2/40), 14.3% (4/28), 16.0% (8/50), and 12.2% (12/98) of normal squamous epithelium, BE, low-, high-grade dysplasia, and EAC tissues, respectively. Enhanced cell growth, proliferation and invasion were observed upon ARID1A knockdown in EAC cells. ARID1A was knocked down in OE33 cells (Sample MS_1 and MS_3) using on-TARGET smartpool ARID1A siRNA. At the same time, OE33 cells were transfected with a non-targeting siRNA, and these experiments (Samples MS_2 and MS_4) functioned as mock controls. Cells were harvested after 48 hours and total RNA was extracted using the Rneasy kit (Qiagen) Aim Affymetrix Human PrimeView Gene Expression Array : to determine the downstream effectors of ARID1A that are likely to contribute to the oncogenic phenotype caused by ARID1A down-regulation. Two biological replicates of each condition (2x ARID1A knockdown, and 2x Mock) were used for the microarray experiment.
Project description:Esophageal cancers (ECs) are highly aggressive tumors with poor prognosis and few treatment options. This study investigated the possibility of treating esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) cells by inhibitors of broad and specific histone deacetylases (HDACi; SAHA, MS-275, FK228) and/or of DNMT (Azacytidine, AZA). Drug targets (HDAC1,2,3 and DNMT1) were present in non-neoplastic (HET-1A), ESCC (OE21) and EAC (OE33) cell lines. All cell lines responded to HDACi by reduced HDAC activity and increased histone acetylation as well as to AZA by up-regulation of p21. Expression of drug targets remained largely unaffected by HDACi and AZA treatment. Importantly, cell viability, apoptosis, cell cycle dynamics and DNA damage were only affected by HDACi and/or AZA in ESCC and EAC, but not the non-neoplastic cells. This was specifically seen for the combination of MS-275 and AZA, leading to enhanced cancer cell selectivity and drug efficiency. By transcriptome analyses of MS-275, AZA and MS-275/AZA treated cells, known (e.g. p21) as well as novel regulated genes significantly associated with the cellular effects post HDACi and/or AZA treatment in ESCC and EAC cells were identified. Finally, human EC tissue specimens frequently expressed the actionable drug targets HDAC1/2/3 and DNMT1. In summary, a combined HDACi (MS-275)/AZA treatment is cancer cell selective and efficient in vitro. Since the majority of ECs express the drug targets in situ, this paves the way for further investigations of HDACi/AZA treatment in esophageal cancer cells and their translation into a clinico-pathological setting. To elucidate the transcriptome response to HDAC inhibitors of normal esophageal cells and esophageal tumor cells, total RNA was isolated from non-neoplastic esophageal epithelial cells (Het1A cells) a well as from two esophageal tumor cell lines (OE21 and OE33), respectively. Cells were treated with either MS-275, Azacytidine (AZA) or in combination of both. DMSO treatment was used as control in each case. Total RNA was isolated from cells 24 h after treatment and experiments were performed in biological triplicates.
Project description:Aims: Cardiac fibroblasts (CFs) play a crucial role in cardiac remodelling, which is a common cause of heart failure (HF). However, the molecular mechanisms underlying the fibroblast-to-myofibroblast transition remain largely unknown. Foxm1 is well known in various cardiopulmonary pathologies. However, Foxm1-driven CF activation in the progression of cardiac remodelling to HF remains to be investigated. Methods: Changes in Foxm1 expression were assessed in samples from patients with HF and mice with transverse aortic constriction (TAC)-induced cardiac remodelling. Pharmacologic antagonist FDI-6 was used to explore the effects of Foxm1 inhibition on post-TAC outcomes. Tcf21-Cre and PostnMCM were used to evaluate Foxm1 loss- and gain-of-function in CFs and myofibroblasts, respectively. Cardiac function and remodelling were examined by echocardiography and histological analysis. Foxm1 downstream target genes were identified by mass spectrometry (MS) and transcriptomic analysis. Post-translational regulation was evaluated by in vitro chromatin immunoprecipitation, co-immunoprecipitation, and ubiquitination assays. Pharmacological inhibition of Usp10 or knockout of p38γ in vivo verified the signalling pathway by which Foxm1 regulated cardiac remodelling. Results: Foxm1 was upregulated in human HF samples as well as in the mouse cardiac remodelling model. CFs were the primary cell type responsible for Foxm1 upregulation. Foxm1 pharmacological inhibition or genetic knockout in CFs or myofibroblasts significantly attenuated TAC-induced cardiac remodelling and HF. Conversely, conditional overexpression of Foxm1 in CFs or myofibroblasts resulted in more severe pathological cardiac remodelling and dysfunction. Combined RNA-sequencing and MS analysis revealed that Foxm1 promoted Usp10 expression by binding to its promoter. Usp10 interacted with p38γ, resulting in p38γ deubiquitination and thus influencing the downstream p38 mitogen-activated protein kinase (MAPK) signalling pathway. Pharmacological inhibition of Usp10 or genetic knockout of p38γ ameliorated the exacerbated TAC-induced cardiac remodelling in mice with myofibroblast-specific Foxm1 overexpression. Conclusion: Our findings reveal an essential role of Foxm1 in CF activation during cardiac remodelling. These results suggest that targeting the Foxm1/Usp10/p38γ MAPK axis may represent a new potential therapeutic strategy against pathological cardiac remodelling and HF.
Project description:Aims: Cardiac fibroblasts (CFs) play a crucial role in cardiac remodelling, which is a common cause of heart failure (HF). However, the molecular mechanisms underlying the fibroblast-to-myofibroblast transition remain largely unknown. Foxm1 is well known in various cardiopulmonary pathologies. However, Foxm1-driven CF activation in the progression of cardiac remodelling to HF remains to be investigated. Methods: Changes in Foxm1 expression were assessed in samples from patients with HF and mice with transverse aortic constriction (TAC)-induced cardiac remodelling. Pharmacologic antagonist FDI-6 was used to explore the effects of Foxm1 inhibition on post-TAC outcomes. Tcf21-Cre and PostnMCM were used to evaluate Foxm1 loss- and gain-of-function in CFs and myofibroblasts, respectively. Cardiac function and remodelling were examined by echocardiography and histological analysis. Foxm1 downstream target genes were identified by mass spectrometry (MS) and transcriptomic analysis. Post-translational regulation was evaluated by in vitro chromatin immunoprecipitation, co-immunoprecipitation, and ubiquitination assays. Pharmacological inhibition of Usp10 or knockout of p38γ in vivo verified the signalling pathway by which Foxm1 regulated cardiac remodelling. Results: Foxm1 was upregulated in human HF samples as well as in the mouse cardiac remodelling model. CFs were the primary cell type responsible for Foxm1 upregulation. Foxm1 pharmacological inhibition or genetic knockout in CFs or myofibroblasts significantly attenuated TAC-induced cardiac remodelling and HF. Conversely, conditional overexpression of Foxm1 in CFs or myofibroblasts resulted in more severe pathological cardiac remodelling and dysfunction. Combined RNA-sequencing and MS analysis revealed that Foxm1 promoted Usp10 expression by binding to its promoter. Usp10 interacted with p38γ, resulting in p38γ deubiquitination and thus influencing the downstream p38 mitogen-activated protein kinase (MAPK) signalling pathway. Pharmacological inhibition of Usp10 or genetic knockout of p38γ ameliorated the exacerbated TAC-induced cardiac remodelling in mice with myofibroblast-specific Foxm1 overexpression. Conclusion: Our findings reveal an essential role of Foxm1 in CF activation during cardiac remodelling. These results suggest that targeting the Foxm1/Usp10/p38γ MAPK axis may represent a new potential therapeutic strategy against pathological cardiac remodelling and HF.