title: Oestrogen causes G2/M arrest and apoptosis in breast cancer cells MDA-MB-231.
abstract: Flavonoids have been shown to exert many biological activities within cancer cells, and oestrogen is known to be structurally related to flavonoids. We investigated the effects of oestrogen in cancer cells to determine if its activities would be similar to those of flavonoids. When 50 microM 17 beta-oestradiol (oestradiol) was added to the oestrogen receptor (ER) alpha-negative breast cancer cell line MDA-MB-231, growth arrest was apparent, similar to that observed with genistein and daidzein. Oestradiol exhibited a dose response curve for the growth arrest similar to those of genistein and daidzein. Apoptosis occurred in the breast cancer cells after treatment with 50 microM oestradiol, genistein, or daidzein, with similar profiles. Flow cytometry analysis revealed that oestradiol treatment caused G2/M arrest and apoptosis. Cell-cycle arrest at G2/M began at 6 h after treatment, and apoptosis began within 24 h. Because MDA-MB-231 cells are ER alpha negative, these results suggest that oestradiol induces cell-cycle arrest and apoptosis through an ER alpha-independent pathway.
authors.affiliation: Department of Health Science, Jichi Medical School, Minamikawachi, Kawachi-gun, Tochigi 329-0498, Japan. nomoto@jichi.ac.jp
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nomoto
authors.forename: Yukitomo
authors.initials: Y
authors.lastname: Arao
authors.forename: Hyogo
authors.initials: H
authors.lastname: Horiguchi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ikeda
authors.forename: Fujio
authors.initials: F
authors.lastname: Kayama
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D004958:Estradiol / Q000494:pharmacology*; D047628:Estrogen Receptor alpha; D004968:Estrogens, Non-Steroidal / Q000494:pharmacology; D005260:Female; D005434:Flow Cytometry; D016195:G2 Phase / Q000187:drug effects*; D019833:Genistein / Q000494:pharmacology; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology; D008938:Mitosis / Q000187:drug effects*; D011960:Receptors, Estrogen / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D047628:Estrogen Receptor alpha; D004968:Estrogens, Non-Steroidal; D007529:Isoflavones; D011960:Receptors, Estrogen; D004958:Estradiol; C004742:daidzein; D019833:Genistein