title: Vitamin D derivatives in combination with 9-cis retinoic acid promote active cell death in breast cancer cells.
abstract: The effects of the novel vitamin D analogue, EB1089 alone, or in combination with the retinoid, 9-cis retinoic acid (9-cis RA) on indices of apoptosis in MCF-7 breast cancer cells have been examined. EB1089 was capable of reducing bcl-2 protein, a suppressor of apoptosis, and increasing p53 protein levels in MCF-7 cell cultures following 96h treatment. In the presence of 9-cis RA, EB1089 acted to further enhance the down-regulation and up-regulation of bcl-2 and p53 respectively. Furthermore, EB1089 induces DNA fragmentation in MCF-7 cells, a key feature of apoptosis, alone and in combination with 9-cis RA in situ. The observation that EB1089 and 9-cis RA act in a cooperative manner to enhance induction of apoptosis in these cells may have therapeutic implications.
authors.affiliation: Department of Clinical Biochemistry, St George's Hospital Medical School, London.
authors.forename: S Y
authors.initials: SY
authors.lastname: James
authors.forename: A G
authors.initials: AG
authors.lastname: Mackay
authors.forename: K W
authors.initials: KW
authors.lastname: Colston
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000473:pathology*; D002117:Calcitriol / Q000031:analogs & derivatives* / Q000494:pharmacology; D004249:DNA Damage; D004273:DNA, Neoplasm / Q000032:analysis; D004357:Drug Synergism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics; D009376:Neoplasms, Hormone-Dependent / Q000473:pathology*; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis / Q000235:genetics
chemical_list: D004273:DNA, Neoplasm; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D014212:Tretinoin; D002117:Calcitriol; C078903:seocalcitol