title: The synthesis of alpha 2-macroglobulin by rat mammary myoepithelial cells is regulated by synergism between glucocorticoids and cytokines.
abstract: Addition of hydrocortisone to the rat mammary gland myoepithelial cell line, G4.2.3, induces the synthesis and secretion of alpha 2-macroglobulin. Interleukin-1 beta, interleukin-6 and transforming growth factor-beta synergize with hydrocortisone, increasing the synthesis of alpha 2-macroglobulin 2- to 4-fold, although they have no effect in the absence of hydrocortisone. Interleukin-6 is the most potent inducer having an optimum concentration of 1 ng/ml. Interleukin-6, unlike interleukin-1 beta or transforming growth factor-beta, decreases the lag phase from 10 h to 4 h before alpha 2-macroglobulin synthesis is induced by hydrocortisone. These results suggest that the mechanism of activation of transcription of the alpha 2-macroglobulin gene in mammary myoepithelial cells might differ from that operating in hepatic cells.
authors.affiliation: Department of Histopathology, St. George's Hospital Medical School, London, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Warburton
authors.forename: B A
authors.initials: BA
authors.lastname: Gusterson
authors.forename: M J
authors.initials: MJ
authors.lastname: O'Hare
mesh_terms: D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000502:physiology*; D004848:Epithelium / Q000378:metabolism; D006854:Hydrocortisone / Q000502:physiology*; D007375:Interleukin-1 / Q000502:physiology; D015850:Interleukin-6 / Q000502:physiology; D008321:Mammary Glands, Animal / Q000378:metabolism*; D051381:Rats; D016212:Transforming Growth Factor beta / Q000502:physiology; D000511:alpha-Macroglobulins / Q000096:biosynthesis*
chemical_list: D016207:Cytokines; D007375:Interleukin-1; D015850:Interleukin-6; D016212:Transforming Growth Factor beta; D000511:alpha-Macroglobulins; D006854:Hydrocortisone