Project description:Naive pluripotent epiblast cells of the preimplantation murine embryo and their in vitro counterpart, embryonic stem (ES) cells, have the capacity to give rise to all cells of the adult. Such developmental plasticity is associated with global genome hypomethylation. It is unclear whether genome methylation is dynamically regulated only via differential expression of DNA methyltransferases (DNMTs) and Ten-eleven Translocation (TET) enzymes, which oxidase methylated DNA. Here we show that LIF/Stat3 signalling induces genomic hypomethylation via metabolic reconfiguration. In Stat3-/- ES cells we observed decreased alpha-ketoglutarate (ɑKG) production from reductive Glutamine metabolism, leading to decreased TET activity, increased Dnmt3a/b expression and to a global increase in DNA methylation. Notably, genome methylation is dynamically controlled by simply modulating αKG availability, mitochondrial activity or Stat3 activation in mitochondria, indicating effective crosstalk between metabolism and the epigenome. Stat3-/- ES cells also show increased methylation at Imprinting Control Regions accompanied with differential expression of >50% of imprinted genes. Single-cell transcriptome analysis of Stat3-/- embryos confirmed dysregulated expression of Dnmt3a/b, Tet2, and imprinted genes in vivo. Our results reveal that the LIF/Stat3 signal bridges the metabolic and epigenetic profiles of naive pluripotent cells, ultimately controlling genome methylation and imprinted gene expression. Several imprinted genes regulate cell proliferation and are often misregulated in tumors. Moreover, a wide range of cancers display Stat3-overactivation, raising the possibility that the molecular module we described here is exploited under pathological conditions.
Project description:RATIONALE: Studying the genes expressed in samples of tissue from patients with cancer may help doctors identify biomarkers related to cancer.
PURPOSE: This laboratory study is using gene expression profiling to evaluate normal tissue and tumor tissue from patients with colon cancer that has spread to the liver, lungs, or peritoneum.
Project description:Gene Expression and DNA methylation profiling in Alzheimer’s Disease patients reveals dysregulated genes associated with site-specific DNA methylation (methylation)
Project description:Hydroxycarbamide (HC), is a cytoreductive drug frequently used to control cell blood counts in patients with myeloproliferative neoplasms (MPNs).To further explore the effects of HC in MPN patients, we performed DNA methylation and gene expression profiling of two differentially developed and clinically relevant cell types, both before and following HC exposure.