title: Evidence that transforming growth factor-beta is a hormonally regulated negative growth factor in human breast cancer cells.
abstract: The hormone-dependent human breast cancer cell line MCF-7 secretes transforming growth factor-beta (TGF-beta), which can be detected in the culture medium in a biologically active form. These polypeptides compete with human platelet-derived TGF-beta for binding to its receptor, are biologically active in TGF-beta-specific growth assays, and are recognized and inactivated by TGF-beta-specific antibodies. Secretion of active TGF-beta is induced 8 to 27-fold under treatment of MCF-7 cells with growth inhibitory concentrations of antiestrogens. Antiestrogen-induced TGF-beta from MCF-7 cells inhibits the growth of an estrogen receptor-negative human breast cancer cell line in coculture experiments; growth inhibition is reversed with anti-TGF-beta antibodies. We conclude that in MCF-7 cells, TGF-beta is a hormonally regulated growth inhibitor with possible autocrine and paracrine functions in breast cancer cells.
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D004965:Estrogen Antagonists / Q000494:pharmacology; D006131:Growth Inhibitors / Q000494:pharmacology; D006801:Humans; D010455:Peptides / Q000378:metabolism* / Q000494:pharmacology; D011956:Receptors, Cell Surface / Q000378:metabolism; D018125:Receptors, Transforming Growth Factor beta; D015291:Transforming Growth Factors
chemical_list: D004965:Estrogen Antagonists; D006131:Growth Inhibitors; D010455:Peptides; D011956:Receptors, Cell Surface; D018125:Receptors, Transforming Growth Factor beta; D015291:Transforming Growth Factors