title: Expression of 5-lipoxygenase in differentiating human skin keratinocytes.
abstract: We studied the expression of arachidonate 5-lipoxygenase (5-LO) in a cell line of human keratinocytes (HaCaT) and in normal human skin keratinocytes in tissue culture. In undifferentiated keratinocytes 5-LO gene expression was low or undetectable as determined by 5-LO mRNA, protein, cell-free enzyme activity, and leukotriene production in intact cells. However, after shift to culture conditions that promote conversion of prokeratinocytes into a more differentiated phenotype, 5-LO gene expression was markedly induced in HaCaT cells and, to a lesser extent, in normal keratinocytes. These results show that 5-LO gene expression is an intrinsic property of human skin keratinocytes.
authors.affiliation: Department of Internal Medicine, University of Heidelberg, Medical School, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Janssen-Timmen
authors.forename: P J
authors.initials: PJ
authors.lastname: Vickers
authors.forename: U
authors.initials: U
authors.lastname: Wittig
authors.forename: W D
authors.initials: WD
authors.lastname: Lehmann
authors.forename: H J
authors.initials: HJ
authors.lastname: Stark
authors.forename: N E
authors.initials: NE
authors.lastname: Fusenig
authors.forename: T
authors.initials: T
authors.lastname: Rosenbach
authors.forename: O
authors.initials: O
authors.lastname: Rådmark
authors.forename: B
authors.initials: B
authors.lastname: Samuelsson
authors.forename: A J
authors.initials: AJ
authors.lastname: Habenicht
mesh_terms: D001094:Arachidonate 5-Lipoxygenase / Q000096:biosynthesis* / Q000235:genetics; D002454:Cell Differentiation; D002460:Cell Line; D002478:Cells, Cultured; D004790:Enzyme Induction; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000032:analysis; D015603:Keratinocytes / Q000378:metabolism*; D007975:Leukotriene B4 / Q000096:biosynthesis; D017997:Leukotriene C4 / Q000096:biosynthesis; D008297:Male; D010413:Penis / Q000166:cytology; D012333:RNA, Messenger / Q000032:analysis; D012867:Skin / Q000166:cytology / Q000378:metabolism*
chemical_list: D006893:Hydroxyeicosatetraenoic Acids; D012333:RNA, Messenger; D007975:Leukotriene B4; D017997:Leukotriene C4; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D001094:Arachidonate 5-Lipoxygenase