Project description:Acetylation enhances TET2 function in protecting against abnormal DNA methylation during oxidative stress [A2780 TET2 KO - methylation]
Project description:Acetylation enhances TET2 function in protecting against abnormal DNA methylation during oxidative stress [shTET2 - H2O2 - methylation]
Project description:Acetylation enhances TET2 function in protecting against abnormal DNA methylation during oxidative stress [A2780 TET2KD damage 3h - methylation]
Project description:Acetylation enhances TET2 function in protecting against abnormal DNA methylation during oxidative stress [A2780 damage time points - methylation]
Project description:DNA methylation is tightly regulated throughout mammalian development and altered methylation patterns are a hallmark of cancer. The methylcytosine dioxygenase TET2 is frequently mutated in acute myeloid leukemia (AML) and has been suggested to protect CpG islands and promoters from aberrant methylation. By generating a novel mouse model of Tet2-deficient AML we show that loss of Tet2 in hematopoietic cells leads to progressive hypermethylation of active enhancer elements and altered expression of genes implicated in tumorigenesis. In contrast, CpG island and promoter methylation does not change in a Tet2-dependent manner. Furthermore, we confirm this specific enhancer hypermethylation phenotype in human AML patients. Thus, we propose that TET2 prevents leukemic transformation of hematopoietic cells by protecting enhancers from aberrant DNA methylation. Gene expression profiles from Tet2-/-;AML1-ETO and Tet2fl/fl;AML1-ETO in vitro-grown hematopoietic cells were compared using GeneChip Mouse Gene ST 2.0 Arrays (Affymetrix). Expression changes were investigated at early (passage 2) and late (passage 10) timepoints after Tet2 disruption.
Project description:DNA methylation is tightly regulated throughout mammalian development and altered methylation patterns are a hallmark of cancer. The methylcytosine dioxygenase TET2 is frequently mutated in acute myeloid leukemia (AML) and has been suggested to protect CpG islands and promoters from aberrant methylation. By generating a novel mouse model of Tet2-deficient AML we show that loss of Tet2 in hematopoietic cells leads to progressive hypermethylation of active enhancer elements and altered expression of genes implicated in tumorigenesis. In contrast, CpG island and promoter methylation does not change in a Tet2-dependent manner. Furthermore, we confirm this specific enhancer hypermethylation phenotype in human AML patients. Thus, we propose that TET2 prevents leukemic transformation of hematopoietic cells by protecting enhancers from aberrant DNA methylation. Enhanced Reduced Representation Bisulfite Sequencing (eRRBS) analysis of in vitro-grown hematopoietic cells transduced with AML1-ETO or MLL-AF9
Project description:DNA methylation is tightly regulated throughout mammalian development and altered methylation patterns are a hallmark of cancer. The methylcytosine dioxygenase TET2 is frequently mutated in acute myeloid leukemia (AML) and has been suggested to protect CpG islands and promoters from aberrant methylation. By generating a novel mouse model of Tet2-deficient AML we show that loss of Tet2 in hematopoietic cells leads to progressive hypermethylation of active enhancer elements and altered expression of genes implicated in tumorigenesis. In contrast, CpG island and promoter methylation does not change in a Tet2-dependent manner. Furthermore, we confirm this specific enhancer hypermethylation phenotype in human AML patients. Thus, we propose that TET2 prevents leukemic transformation of hematopoietic cells by protecting enhancers from aberrant DNA methylation. 5hmC-DIP-seq analysis for distribution of 5hmC in in vitro-grown hematopoietic cells transduced with AML1-ETO
Project description:DNA methylation is tightly regulated throughout mammalian development and altered methylation patterns are a hallmark of cancer. The methylcytosine dioxygenase TET2 is frequently mutated in acute myeloid leukemia (AML) and has been suggested to protect CpG islands and promoters from aberrant methylation. By generating a novel mouse model of Tet2-deficient AML we show that loss of Tet2 in hematopoietic cells leads to progressive hypermethylation of active enhancer elements and altered expression of genes implicated in tumorigenesis. In contrast, CpG island and promoter methylation does not change in a Tet2-dependent manner. Furthermore, we confirm this specific enhancer hypermethylation phenotype in human AML patients. Thus, we propose that TET2 prevents leukemic transformation of hematopoietic cells by protecting enhancers from aberrant DNA methylation. ChIP-seq analysis for distribution of H3K4me1, H3K27ac, and H3K4me3 histone marks in in vitro-grown hematopoietic cells transduced with AML1-ETO
Project description:DNA methylation is tightly regulated throughout mammalian development and altered DNA methylation patterns are a general hallmark of cancer. The methylcytosine dioxygenase TET2 is frequently mutated in hematological disorders, including acute myeloid leukemia (AML), and has been suggested to protect CpG islands and promoters from aberrant DNA methylation. In this study, we present a novel Tet2-dependent leukemia mouse model that closely recapitulates gene expression profiles and hallmarks of human AML1-ETO induced AML. Using this model, we show that the primary effect of Tet2 loss in pre-leukemic hematopoietic cells is progressive and widespread DNA hypermethylation affecting up to 25% of active enhancer elements. In contrast, CpG island and promoter methylation does not change in a Tet2-dependent manner, but increase relative to population doublings. We confirm this specific enhancer hypermethylation phenotype in human AML patients with TET2 mutations. Analysis of immediate gene expression changes reveals rapid deregulation of a large number of genes implicated in tumorigenesis, including many downregulated tumor suppressor genes. Hence, we propose that TET2 prevents leukemic transformation by protecting enhancers from aberrant DNA methylation, and that it is the combined silencing of several tumor suppressor genes in TET2-mutated hematopoietic cells that contribute to increased stem cell proliferation and leukemogenesis. Gene expression profiles (Agilent SurePrint G3 Mouse GE 8x60K arrays) of FACS-sorted in vivo GMP cells (Lin-cKit+Sca1-CD16/32+CD150-) isolated from bone marrow of recipient mice one month after transplantation of WT bone marrow or splenic cells from two independent moribond Tet2-/-:AE leukemic mice (LeuA/AE1), or LeuB/AE3)