title: Identification of unique synergistic drug combinations associated with downexpression of survivin in a preclinical breast cancer model system.
abstract: An in-vitro 72-h assay using median effect analysis and curve shift analysis was used to evaluate the utility of potentially clinically useful combinations of agents for synergism or antagonism. Six human breast cancer cell lines, both receptor rich and receptor poor, were studied.Panobinostat (LBH-589), a pan histone deacetylase inhibitor with a multitude of biological effects, exhibits time-dependent synergistic effects in breast cancer cell lines with docetaxel, doxorubicin, or gemcitabine in clinically relevant concentrations. Survivin expression was markedly downregulated in the presence of panobinostat with gemcitabine. Bortezomib, a proteasome inhibitor,markedly enhanced the cytotoxic effects of panobinostat combined with gemcitabine. Panobinostat did not demonstrate universal enhancement of cytotoxic drugs,and therefore, synergy was dependent on the second agent selected. No synergy was noted with anti-Her2 agents in Her2 overexpressing cell lines. Metformin combined with panobinostat demonstrated no synergy in this test system. These effects were confirmed by an apoptosis assay and caspase-3 production. A positive drug interaction was identified. The triplet of panobinostat with either doxorubicin/carboplatin or gemcitabine/carboplatin was especially potent in all cell lines. As all these agents are clinically available, further studies of the potent combinations are warranted.
authors: Section of Experimental Therapeutics, Don Monti Division of Oncology, Monter Cancer Center, Lake Success, NY 1104, USA. budman@nshs.edu
authors: Daniel R
authors: DR
authors: Budman
authors: Anthony
authors: A
authors: Calabro
authors: Lisa
authors: L
authors: Rosen
authors: Martin
authors: M
authors: Lesser
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D016190:Carboplatin / Q000008:administration & dosage; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D000077143:Docetaxel; D015536:Down-Regulation / Q000187:drug effects; D004317:Doxorubicin / Q000008:administration & dosage / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D005229:Fatty Acids, Monounsaturated / Q000008:administration & dosage; D005260:Female; D000077340:Fluvastatin; D006801:Humans; D006877:Hydroxamic Acids / Q000008:administration & dosage / Q000494:pharmacology; D007211:Indoles / Q000008:administration & dosage / Q000494:pharmacology; D051034:Inhibitor of Apoptosis Proteins / Q000378:metabolism*; D000077767:Panobinostat; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D000077022:Survivin; D043823:Taxoids / Q000008:administration & dosage / Q000494:pharmacology; D000093542:Gemcitabine
chemical_list: D016190:Carboplatin; D053148:Caspase 3; D003841:Deoxycytidine; D000077143:Docetaxel; D004317:Doxorubicin; D005229:Fatty Acids, Monounsaturated; D000077340:Fluvastatin; D006877:Hydroxamic Acids; D007211:Indoles; D051034:Inhibitor of Apoptosis Proteins; D000077767:Panobinostat; D018719:Erb-b2 Receptor Tyrosine Kinases; D000077022:Survivin; D043823:Taxoids; D000093542:Gemcitabine; C107489:BIRC5 protein, human; C508053:ERBB2 protein, human