title: Loss of imprinting of IGF2 and not H19 in breast cancer, adjacent normal tissue and derived fibroblast cultures.
abstract: Insulin-like growth factors are involved in the paracrine growth regulation of human breast tumor cells. IGF2 is imprinted in most tissues, and shows expression of the paternal allele only. To investigate whether disruption of this monoallelic IGF2 expression is involved in breast cancer development, a series of primary tumors and adjacent, histologically normal, breast tissue samples, as well as matched primary in vitro fibroblast cultures were studied. Biallelic expression (partial) of IGF2 was found in the majority of in vivo samples, and corresponding fibroblast cultures, while monoallelic expression was found in a normal breast sample. In contrast, H19, a closely apposed, but reciprocally imprinted gene, assumed to be regulated by a common control element, showed retention of monoallelic H19 expression in all in vivo and in the majority of in vitro samples. These data indicate that IGF2, but not H19, is prone to loss of imprinting in breast cancer.
authors.affiliation: Department of Medical Oncology, Daniel den Hoed Cancer Center/Academic Hospital, Rotterdam, The Netherlands.
authors.forename: C E
authors.initials: CE
authors.lastname: van Roozendaal
authors.forename: A J
authors.initials: AJ
authors.lastname: Gillis
authors.forename: J G
authors.initials: JG
authors.lastname: Klijn
authors.forename: B
authors.initials: B
authors.lastname: van Ooijen
authors.forename: C J
authors.initials: CJ
authors.lastname: Claassen
authors.forename: A M
authors.initials: AM
authors.lastname: Eggermont
authors.forename: S C
authors.initials: SC
authors.lastname: Henzen-Logmans
authors.forename: J W
authors.initials: JW
authors.lastname: Oosterhuis
authors.forename: J A
authors.initials: JA
authors.lastname: Foekens
authors.forename: L H
authors.initials: LH
authors.lastname: Looijenga
mesh_terms: D001940:Breast / Q000378:metabolism*; D001943:Breast Neoplasms / Q000235:genetics*; D002478:Cells, Cultured; D005347:Fibroblasts / Q000378:metabolism; D018392:Genomic Imprinting; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D009124:Muscle Proteins / Q000378:metabolism*; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
chemical_list: C094335:H19 long non-coding RNA; D009124:Muscle Proteins; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D007335:Insulin-Like Growth Factor II