Modulation by oestrogen and progestins/antiprogestins of alpha interferon receptor expression in human breast cancer cells.
Human breast cancer ZR-75-1 cells expressed 1516 (105) (mean [S.D.]) interferon (IFN) receptors (IFNR) per cell with Kd of 0.61 (0.15) nmol/l. Oestrogen independent ZR-PR-LT and tamoxifen resistant ZR-75-9a1 8 mumol/l cells expressed similar numbers of IFNR. ZR-75-9a1 cells, which had been maintained in the absence of tamoxifen or known oestrogenic activity for 46 weeks, expressed a significantly higher number of IFNR (3170 [315]). Exposure of ZR-75-1 cells to 10(-9) mol/l 17 beta-oestradiol (E2) led to a consistent reduction in IFNR numbers whilst 10(-6) mol/l tamoxifen slightly increased IFNR expression. Since IFN increases oestrogen receptors in this cell line, IFN and E2 appear to have opposite effects on expression of each others' receptor. 10(-9) mol/l medroxy progesterone acetate and mifepristone significantly increased IFNR numbers whilst ORG 2058 decreased IFNR expression and ZK 98.299 had no effect. Progestin/antiprogestin induced IFNR increase in this cell line correlated with down-regulation of progesterone receptor (PR). Thus an IFN/ER/PR axis may exist in ZR-75-1 cells and variants.
Martin
J H
JH
Department of Therapeutics and Pharmacology, Royal Victoria Hospital, Queen's University of Belfast, Northern Ireland, U.K.
McKibben
B M
BM
Lynch
M
M
van den Berg
H W
HW
D001943:Breast Neoplasms / Q000737:chemistry*; D002460:Cell Line; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006801:Humans; D045167:Progesterone Congeners / Q000494:pharmacology*; D011372:Progestins / Q000037:antagonists & inhibitors; D011960:Receptors, Estrogen / Q000032:analysis; D011971:Receptors, Immunologic / Q000032:analysis / Q000187:drug effects*; D017471:Receptors, Interferon; D011980:Receptors, Progesterone / Q000032:analysis; D014407:Tumor Cells, Cultured / Q000737:chemistry
D045167:Progesterone Congeners; D011372:Progestins; D011960:Receptors, Estrogen; D011971:Receptors, Immunologic; D017471:Receptors, Interferon; D011980:Receptors, Progesterone; D004958:Estradiol