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CamptothecinTopoisomerase I InhibitorsDNA Topoisomerases, Type IAntineoplastic Agents, PhytogenicDrug ResistanceTopotecanTumor Cells, CulturedTopoisomerase InhibitorsTeniposideDNA DamageCamptothecaLeukemia L1210Leukemia P388Antineoplastic AgentsDrug Resistance, NeoplasmCell LineCell Line, TumorDrug Screening Assays, AntitumorTopoisomerase II InhibitorsEtoposideApoptosisOrganosilicon CompoundsDrug Resistance, MultipleDNA Topoisomerases, Type IIRubiaceaeEnzyme InhibitorsCell SurvivalAphidicolinDoxorubicinOrganic Chemistry PhenomenaP-GlycoproteinDNA, NeoplasmNeoplasm TransplantationDNACell DivisionKB CellsDNA, SuperhelicalCell CycleClone CellsMice, NudeAmsacrineNeoplasm ProteinsNeoplasms, ExperimentalBase SequenceDNA CleavageColonic NeoplasmsLung NeoplasmsRNA, MessengerAntibiotics, AntineoplasticMutationDNA ReplicationIridoid GlucosidesDNA RepairKineticsCisplatinTumor Suppressor Protein p53Folic Acid AntagonistsMolecular Sequence DataIntercalating AgentsCricetinaeDose-Response Relationship, DrugNeoplasm MetastasisLeukemia L5178TransfectionEllipticinesRNA, NeoplasmDaunorubicinLeukemia, ExperimentalCricetulusATP-Binding Cassette TransportersSecondary MetabolismKaryotypingProstatic NeoplasmsLactonesPodophyllotoxinDNA-Binding ProteinsChemistry, OrganicGlyoxalGene ExpressionCarubicinMultidrug Resistance-Associated ProteinsFlow CytometryTrimetrexateMelanomaTransplantation, HeterologousBreast NeoplasmsAclarubicinPoly(ADP-ribose) PolymerasesBlotting, WesternPhenotypeGene Expression Regulation, NeoplasticMammary Neoplasms, ExperimentalMelanoma, ExperimentalNeoplasmsIndenesNaphthoquinonesS PhaseRadiation ToleranceGene AmplificationIridoids
Resistance to camptothecinTopotecanAnticancerEtoposideMutationsTopoisomeraseBreast cancerCellHuman
Resistance to camptothecin4
  • 6. Altered topoisomerase I expression in two subclones of human CEM leukemia selected for resistance to camptothecin. (nih.gov)
  • 17. Engineered resistance to camptothecin and antifolates by retroviral coexpression of tyrosyl DNA phosphodiesterase-I and thymidylate synthase. (nih.gov)
  • 19. Cross-resistance to camptothecin analogues in a mitoxantrone-resistant human breast carcinoma cell line is not due to DNA topoisomerase I alterations. (nih.gov)
  • Mutations that impart resistance to camptothecin have been identified in several regions of human topoisomerase I. We present the crystal structures of two camptothecin-resistant forms of human topoisomerase I (Phe361Ser at 2.6A resolution and Asn722Ser at 2.3A resolution) in ternary complexes with DNA and topotecan (Hycamtin), a camptothecin analogue currently in widespread clinical use. (nih.gov)
Topotecan1
Anticancer2
  • 16. Enhancing the anticancer efficacy of camptothecin using biotinylated poly(ethylene glycol) conjugates in sensitive and multidrug-resistant human ovarian carcinoma cells. (nih.gov)
  • This enzyme is the sole target of the camptothecin family of anticancer compounds, which acts by stabilizing the covalent protein-DNA complex and enhancing apoptosis through blocking the advancement of replication forks. (nih.gov)
Etoposide1
  • The apoptotic inducers including actinomycin D, camptothecin and etoposide are also the chemotherapeutic drugs in clinical cancer therapy and PTMA siRNA can accelerate apoptotic progression in cells treated with those apoptosis inducers. (biomedcentral.com)
Mutations2
  • 4. Identification of mutations at DNA topoisomerase I responsible for camptothecin resistance. (nih.gov)
  • We further consider camptothecin-resistant mutations at seven additional sites in human topoisomerase I and present structural evidence explaining their possible impact on drug binding. (nih.gov)
Topoisomerase8
  • 1. Novel mutation of topoisomerase I in rendering cells resistant to camptothecin. (nih.gov)
  • 2. Characterization of a novel topoisomerase I mutation from a camptothecin-resistant human prostate cancer cell line. (nih.gov)
  • 3. DNA repair enzyme, O6-methylguanine DNA methyltransferase, modulates cytotoxicity of camptothecin-derived topoisomerase I inhibitors. (nih.gov)
  • 8. Differential GADD45, p21CIP1/WAF1, MCL-1 and topoisomerase II gene induction and secondary DNA fragmentation after camptothecin-induced DNA damage in two mutant p53 human colon cancer cell lines. (nih.gov)
  • 10. Development of a stable camptothecin-resistant subline of P388 leukemia with reduced topoisomerase I content. (nih.gov)
  • 11. Use of camptothecin-resistant mammalian cell lines to evaluate the role of topoisomerase I in the antiproliferative activity of the indolocarbazole, NB-506, and its topoisomerase I binding site. (nih.gov)
  • 12. Increased expression of DNA topoisomerase I gene and collateral sensitivity to camptothecin in human cisplatin-resistant bladder cancer cells. (nih.gov)
  • 18. Acquired camptothecin resistance of human breast cancer MCF-7/C4 cells with normal topoisomerase I and elevated DNA repair. (nih.gov)
Breast cancer1
  • Selected compounds were primarily evaluated for their antiproliferative activities against five human tumor cell lines including lung carcinoma (A549), triple-negative breast cancer (MDA-MB-231), estrogen receptor-positive and HER2-negative breast cancer (MCF-7), as well as HeLa (cervical carcinoma)-derived (KB) and its multidrug-resistant (MDR) subline (KB-VIN). (technologynetworks.com)
Cell2
  • 5. Camptothecin resistance involving steps subsequent to the formation of protein-linked DNA breaks in human camptothecin-resistant KB cell lines. (nih.gov)
  • These results advance our understanding of the mechanism of cell poisoning by camptothecin and suggest specific modifications to the drug that may improve efficacy. (nih.gov)
Human1
  • 13. Correlations between S and G2 arrest and the cytotoxicity of camptothecin in human colon carcinoma cells. (nih.gov)