title: Decreased expression of cell proliferation-related genes in clonally derived skin fibroblasts from children with Silver-Russell syndrome is independent of the degree of 11p15 ICR1 hypomethylation.
abstract: BACKGROUND
  The in vitro analysis of the hypomethylation of imprinting control region 1 (ICR1) within the IGF2/H19 locus is challenged by the mosaic distribution of the epimutation in tissues from children with Silver-Russell syndrome (SRS). To exclude mosaicism, clonal cultures of skin fibroblasts from four children with SRS and three controls were analyzed. Cell proliferation, IGF-II secretion, and IGF2 and H19 expression were measured, and a microarray expression analysis was performed.
  
  
  RESULTS
  Single-cell expansion established severely ICR1 hypomethylated clones (SRShypo) and normomethylated clones (SRSnormo) from the patients and controls (Cnormo). IGF2 expression was below the detection limit of the quantitative real-time PCR (qRT-PCR) assay, whereas H19 expression was detectable, without differences between fibroblast clones. Cell count-related IGF-II release was comparable in SRShypo and Cnormo supernatants. Cell proliferation was diminished in SRShypo compared to Cnormo (p = 0.035). The microarray analysis revealed gene expression changes in SRS clones, predicting a decrease in cell proliferation and a delay in mitosis.
  
  
  CONCLUSIONS
  The analysis of severely ICR1 hypomethylated clonal fibroblasts did not reveal functional differences compared to normomethylated clones with respect to IGF2 and H19 expression. A difference compared to the clones from healthy individuals was present in the form of a lower proliferation rate, presumably due to impaired cell cycle progression.
authors: Pediatric Endocrinology, University Children's Hospital Tuebingen, Hoppe-Seyler-Straße 1, 72076 Tuebingen, Germany.
authors: Doreen
authors: D
authors: Heckmann
authors: Pediatric Endocrinology, University Children's Hospital Tuebingen, Hoppe-Seyler-Straße 1, 72076 Tuebingen, Germany.
authors: Christina
authors: C
authors: Urban
authors: Pediatric Endocrinology, University Children's Hospital Tuebingen, Hoppe-Seyler-Straße 1, 72076 Tuebingen, Germany.
authors: Karin
authors: K
authors: Weber
authors: Pediatric Endocrinology, University Children's Hospital Tuebingen, Hoppe-Seyler-Straße 1, 72076 Tuebingen, Germany.
authors: Kai
authors: K
authors: Kannenberg
authors: Pediatric Endocrinology, University Children's Hospital Tuebingen, Hoppe-Seyler-Straße 1, 72076 Tuebingen, Germany.
authors: Gerhard
authors: G
authors: Binder
keywords: Fibroblasts; H19; IGF2; Methylation; Silver-Russell syndrome
references: Best Pract Res Clin Endocrinol Metab. 2011 Feb;25(1):153-60
references: 21396582
references: Nat Genet. 2008 Aug;40(8):971-6
references: 18587395
references: Nucleic Acids Res. 2005 Aug 16;33(14):e128
references: 16106041
references: Proc Natl Acad Sci U S A. 1999 Mar 30;96(7):3706-11
references: 10097101
references: Epigenomics. 2011 Oct;3(5):625-37
references: 22126250
references: Cancer Res. 2010 Apr 15;70(8):3140-9
references: 20388800
references: Nat Cell Biol. 2012 Jun 10;14(7):659-65
references: 22684254
references: Nat Genet. 2005 Sep;37(9):1003-7
references: 16086014
references: Hum Mol Genet. 2009 Dec 15;18(24):4724-33
references: 19755383
references: Clin Genet. 2012 Apr;81(4):366-77
references: 22248018
references: Cell. 1993 Oct 8;75(1):73-82
references: 8402902
references: Exp Cell Res. 1993 Jan;204(1):22-9
references: 8380141
references: Clin Genet. 2011 Jul;80(1):83-8
references: 20738330
references: Eur J Hum Genet. 2001 Jun;9(6):409-18
references: 11436121
references: Nat Commun. 2013;4:1479
references: 23403580
references: Epigenetics. 2010 Jul 1;5(5):373-7
references: 20495355
references: Mol Reprod Dev. 1994 Jul;38(3):239-46
references: 7917273
references: Nucleic Acids Res. 2006 Mar 31;34(6):1765-71
references: 16582102
references: Clin Epigenetics. 2012 Sep 18;4(1):15
references: 22989232
references: Cytogenet Genome Res. 2006;113(1-4):188-93
references: 16575179
references: Nature. 2000 May 25;405(6785):482-5
references: 10839546
references: PLoS One. 2007 Sep 05;2(9):e845
references: 17786216
references: Hum Mutat. 2014 Oct;35(10):1211-20
references: 25044976
references: J Clin Endocrinol Metab. 2006 Nov;91(11):4709-12
references: 16940449
references: Nature. 2000 May 25;405(6785):486-9
references: 10839547
references: FEBS Lett. 2005 Jul 4;579(17):3849-54
references: 15978578
references: RNA. 2007 Mar;13(3):313-6
references: 17237358
references: Cell Death Differ. 2013 Jun;20(6):800-11
references: 23429262