title: Ascorbate promotes epigenetic activation of CD30 in human embryonic stem cells.
abstract: Human embryonic stem cells (hESCs) and induced pluripotent stem cells have the ability to adapt to various culture conditions. Phenotypic and epigenetic changes brought about by the culture conditions can, however, have significant impacts on their use in research and in clinical applications. Here, we show that diploid hESCs start to express CD30, a biomarker for malignant cells in Hodgkin's disease and embryonal carcinoma cells, when cultured in knockout serum replacement (KOSR)-based medium, but not in fetal calf serum containing medium. We identify the commonly used medium additive, ascorbate, as the sole medium component in KOSR responsible for CD30 induction. Our data show that this epigenetic activation of CD30 expression in hESCs by ascorbate occurs through a dramatic loss of DNA methylation of a CpG island in the CD30 promoter. Analysis of the phenotype and transcriptome of hESCs that overexpress the CD30 signaling domain reveals that CD30 signaling leads to inhibition of apoptosis, enhanced single-cell growth, and transcriptome changes that are associated with cell signaling, lipid metabolism, and tissue development. Collectively, our data show that hESC culture media that contain ascorbate trigger CD30 expression through an epigenetic mechanism and that this provides a survival advantage and transcriptome changes that may help adapt hESCs to in vitro culture conditions.
authors: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Queensland, Australia.
authors: Tung-Liang
authors: TL
authors: Chung
authors: Jennifer P
authors: JP
authors: Turner
authors: Nilay Y
authors: NY
authors: Thaker
authors: Gabriel
authors: G
authors: Kolle
authors: Justin J
authors: JJ
authors: Cooper-White
authors: Sean M
authors: SM
authors: Grimmond
authors: Martin F
authors: MF
authors: Pera
authors: Ernst J
authors: EJ
authors: Wolvetang
mesh_terms: D001205:Ascorbic Acid / Q000494:pharmacology*; D002460:Cell Line; D018899:CpG Islands / Q000235:genetics; D053595:Embryonic Stem Cells / Q000187:drug effects* / Q000378:metabolism*; D044127:Epigenesis, Genetic / Q000187:drug effects* / Q000235:genetics; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D007621:Karyotyping; D017730:Ki-1 Antigen / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics
chemical_list: D017730:Ki-1 Antigen; D001205:Ascorbic Acid