title: Insulin-like growth factor binding protein-3 in breast cyst fluid: relationships with insulin-like growth factors I and II and transforming growth factor-beta 1 and 2.
abstract: Women who have palpable breast cysts with intracystic Na/K > 3 may have a lower risk of developing breast cancer than those with intracystic Na/K < 3. In this study significantly higher concentrations of insulin-like growth factor-binding protein-3 (IGFBP-3), insulin-like growth factors I and II (IGF-I, IGF-II) and transforming growth factor-beta 2 (TGF-beta2) were found in the Na/K > 3 sub-group. No difference was found in transforming-growth factor-beta 1 (TGF-beta1) levels between the two sub-groups of breast cysts. A positive correlation was obtained for IGFBP-3 and TGF-beta1 in the Na/ K > 3 sub-group consistent with reports that TGF-beta1 may regulate the production of IGFBP-3. Equimolar amounts of total IGFs and IGFBP-3 in breast cyst fluid imply that most, if not all, of these IGFs are protein-bound. The significantly higher concentrations of TGF-beta2 in the Na/K > 3 sub-group may partly explain the lower risk of breast cancer in this group of women.
authors.affiliation: Department of Clinical Biochemistry, Freeman Hospital, Newcastle upon Tyne, UK.
authors.forename: L C
authors.initials: LC
authors.lastname: Lai
authors.forename: H
authors.initials: H
authors.lastname: Erbas
authors.forename: K A
authors.initials: KA
authors.lastname: Meadows
authors.forename: T W
authors.initials: TW
authors.lastname: Lennard
authors.forename: J M
authors.initials: JM
authors.lastname: Holly
mesh_terms: D005122:Exudates and Transudates / Q000737:chemistry; D005260:Female; D005348:Fibrocystic Breast Disease / Q000737:chemistry* / Q000145:classification; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000032:analysis*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D007335:Insulin-Like Growth Factor II / Q000032:analysis*; D011188:Potassium / Q000032:analysis; D012964:Sodium / Q000032:analysis; D016212:Transforming Growth Factor beta / Q000032:analysis*
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D016212:Transforming Growth Factor beta; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II; D012964:Sodium; D011188:Potassium