title: Proliferation kinetics of a human breast cancer line in vitro following treatment with 17beta-estradiol and 1-beta-D-arabinofuranosylcytosine.
abstract: The effect of 17beta-estradiol on an estrogen receptor-positive human breast cancer cell line (MCF-7) was studied. Low concentrations (10(-9) M) of 17beta-estradiol enhanced the rate of cell proliferation; the overall cell cycle time was shortened; and the proportion of cells in the S phase increased. Higher concentrations (10(-7) M) suppressed proliferation and slightly decreased the proportion of the cells in DNA synthesis. When combined with 1-beta-D-arabinofuranosylcytosine, an S-phase-specific chemotherapeutic agent, 10(-9) M 17beta-estradiol enhanced cell killing. This enhancement was not observed with 10(-7) M 17beta-estradiol. Kinetic changes caused by hormones have profound implications in clinical therapy, since the efficacy of cycle active agents may be altered.
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003561:Cytarabine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007700:Kinetics; D009374:Neoplasms, Experimental / Q000188:drug therapy; D011960:Receptors, Estrogen
chemical_list: D011960:Receptors, Estrogen; D003561:Cytarabine; D004958:Estradiol