title: Selective killing of adriamycin-resistant (G2 checkpoint-deficient and MRP1-expressing) cancer cells by docetaxel.
abstract: Chemotherapy of cancer is limited by toxicity to normal cells. Drug resistance further limits the therapy. Here, we investigated selective killing of drug-resistant cancer cells by antagonistic drug combinations, which can spare (because of drug antagonism) normal cells. We used paired cell lines that are resistant to Adriamycin due to either expression of MRP1 or lack of G2 checkpoints. The goal was to selectively kill Adriamycin-resistant cancer cells with Docetaxel (Taxotere), while protecting parental (Adriamycin-sensitive) cells, using cytostatic concentrations of Adriamycin. Taxotere kills cells in mitosis. Therefore, by arresting parental cells in G2, 20 to 40 ng/mL of Adriamycin prevented cell death caused by Taxotere. Also, Adriamycin prevented the effects of Taxotere in normal human lymphocytes. In contrast, Taxotere selectively killed MRP1-expressing leukemia cells, which did not undergo G2 arrest in the presence of Adriamycin. Also, in the presence of Adriamycin, HCT116-p21-/- cancer cells with a defective G2 checkpoint entered mitosis and were selectively killed by Taxotere. Finally, 20 ng/mL of Adriamycin protected normal FDC-P1 hematopoietic cells from Taxotere. Whereas parental cells were protected by Adriamycin, the mitogen-activated protein/extracellular signal-regulated kinase inhibitor PD90598 potentiated the cytotoxic effect of Taxotere selectively in Raf-1-transformed FDC-P1 leukemia cells. We propose a therapeutic strategy to prevent normal cells from entering mitosis while increasing apoptosis selectively in mitotic cancer cells.
authors.affiliation: Brander Cancer Research Institute, New York Medical College, Valhalla, New York, USA.
authors.forename: Zoya N
authors.initials: ZN
authors.lastname: Demidenko
authors.forename: Dorota
authors.initials: D
authors.lastname: Halicka
authors.forename: Jan
authors.initials: J
authors.lastname: Kunicki
authors.forename: James A
authors.initials: JA
authors.lastname: McCubrey
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Darzynkiewicz
authors.forename: Mikhail V
authors.initials: MV
authors.lastname: Blagosklonny
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000077143:Docetaxel; D004317:Doxorubicin / Q000008:administration & dosage / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology; D016195:G2 Phase / Q000502:physiology*; D045325:HCT116 Cells; D018922:HL-60 Cells; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D020930:MAP Kinase Kinase Kinases / Q000037:antagonists & inhibitors; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000096:biosynthesis*; D019908:Proto-Oncogene Proteins c-raf / Q000235:genetics; D043823:Taxoids / Q000008:administration & dosage / Q000494:pharmacology*; D014162:Transfection
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D000077143:Docetaxel; D004317:Doxorubicin; D005419:Flavonoids; D020930:MAP Kinase Kinase Kinases; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D019908:Proto-Oncogene Proteins c-raf; D043823:Taxoids; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; C421109:multidrug resistance-associated protein 1