title: Interleukin-1 directly regulates hormone-dependent human breast cancer cell proliferation in vitro.
abstract: Direct in vitro effects of IL-1 on hormone-dependent (MCF-7 and ZR-75-B) and independent (HS-578-T and MDA-231) human breast cancer cell proliferation were investigated in short-term and long-term cell cultures. For short-term (48 h) studies [3H]thymidine uptake was used as an index of proliferation, while for long-term (12 day) cultures actual cell numbers were determined. Initial studies, conducted with MCF-7 cells, demonstrated that both forms of recombinant human IL-1 (alpha and beta) at 10(-11) M inhibited [3H]thymidine uptake by MCF-7 by 70%, and by day 7 of the long-term study alpha and beta IL-1 at 10(-11) M inhibited MCF-7 cell growth by 80%. IL-1, while inhibiting the growth of another hormone-dependent breast cancer cell line; ZR-75-B, had no effect on the hormone-independent cell lines MDA-231 and HS-578-T. The differing proliferative responses of the hormone-dependent and independent cells to IL-1 may, in part, be due to the expression of IL-1 receptors on these cells, in that MCF-7 cells express IL-1 receptors [dissociation constant (Kd) = 2.0 x 10(-10) M; receptor density = 2,500 sites per cell and mol wt = 80,000] while the hormone-independent MDA-231 cells do not.
authors.affiliation: Clinical Psychobiology Branch, National Institute of Mental Health, Bethesda, Maryland 20892.
authors.forename: G F
authors.initials: GF
authors.lastname: Paciotti
authors.forename: L
authors.initials: L
authors.lastname: Tamarkin
mesh_terms: D001667:Binding, Competitive; D001943:Breast Neoplasms / Q000188:drug therapy*; D002455:Cell Division / Q000187:drug effects; D005260:Female; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D007553:Isotope Labeling; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy*; D011971:Receptors, Immunologic / Q000502:physiology; D017472:Receptors, Interleukin-1; D013936:Thymidine / Q000378:metabolism; D014316:Tritium / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D007375:Interleukin-1; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D014316:Tritium; D013936:Thymidine