Abstract
To resolve the topological problems that threaten the function and structural integrity of nuclear and mitochondrial genomes and RNA molecules, human cells encode six different DNA topoisomerases including type IB enzymes (TOP1 and TOP1mt), type IIA enzymes (TOP2α and TOP2β) and type IA enzymes (TOP3α and TOP3β). DNA entanglements and the supercoiling of DNA molecules are regulated by topoisomerases through the introduction of transient enzyme-linked DNA breaks. The covalent topoisomerase–DNA complexes are the cellular targets of a diverse group of cancer chemotherapeutics, which reversibly stabilize these reaction intermediates. Here we review the structure–function and catalytic mechanisms of each family of eukaryotic DNA topoisomerases and the topoisomerase-targeting agents currently approved for patient therapy or in clinical trials, and highlight novel developments and challenges in the clinical development of these agents.
Similar content being viewed by others
References
Wang JC (1971) Interaction between DNA and an Escherichia coli protein omega. J Mol Biol 55(3):523–533
Champoux JJ, Dulbecco R (1972) An activity from mammalian cells that untwists superhelical DNA–a possible swivel for DNA replication (polyoma-ethidium bromide-mouse-embryo cells-dye binding assay). Proc Natl Acad Sci USA 69(1):143–146
Champoux JJ (1981) DNA is linked to the rat liver DNA nicking-closing enzyme by a phosphodiester bond to tyrosine. J Biol Chem 256(10):4805–4809
Zhang H, Barcelo JM, Lee B, Kohlhagen G, Zimonjic DB, Popescu NC, Pommier Y (2001) Human mitochondrial topoisomerase I. Proc Natl Acad Sci USA 98(19):10608–10613. doi:10.1073/pnas.191321998
Gellert M, Mizuuchi K, O’Dea MH, Nash HA (1976) DNA gyrase: an enzyme that introduces superhelical turns into DNA. Proc Natl Acad Sci USA 73(11):3872–3876
Mizuuchi K, Fisher LM, O’Dea MH, Gellert M (1980) DNA gyrase action involves the introduction of transient double-strand breaks into DNA. Proc Natl Acad Sci USA 77(4):1847–1851
Liu LF, Liu CC, Alberts BM (1980) Type II DNA topoisomerases: enzymes that can unknot a topologically knotted DNA molecule via a reversible double-strand break. Cell 19(3):697–707
Austin CA, Fisher LM (1990) Isolation and characterization of a human cDNA clone encoding a novel DNA topoisomerase II homologue from HeLa cells. FEBS Lett 266(1–2):115–117
Baldi MI, Benedetti P, Mattoccia E, Tocchini-Valentini GP (1980) In vitro catenation and decatenation of DNA and a novel eucaryotic ATP-dependent topoisomerase. Cell 20(2):461–467
Chung TD, Drake FH, Tan KB, Per SR, Crooke ST, Mirabelli CK (1989) Characterization and immunological identification of cDNA clones encoding two human DNA topoisomerase II isozymes. Proc Natl Acad Sci USA 86(23):9431–9435
Drake FH, Zimmerman JP, McCabe FL, Bartus HF, Per SR, Sullivan DM, Ross WE, Mattern MR, Johnson RK, Crooke ST et al (1987) Purification of topoisomerase II from amsacrine-resistant P388 leukemia cells. Evidence for two forms of the enzyme. J Biol Chem 262(34):16739–16747
Miller KG, Liu LF, Englund PT (1981) A homogeneous type II DNA topoisomerase from HeLa cell nuclei. J Biol Chem 256(17):9334–9339
Kim RA, Wang JC (1992) Identification of the yeast TOP3 gene product as a single strand-specific DNA topoisomerase. J Biol Chem 267(24):17178–17185
Wallis JW, Chrebet G, Brodsky G, Rolfe M, Rothstein R (1989) A hyper-recombination mutation in S. cerevisiae identifies a novel eukaryotic topoisomerase. Cell 58(2):409–419
Hanai R, Caron PR, Wang JC (1996) Human TOP3: a single-copy gene encoding DNA topoisomerase III. Proc Natl Acad Sci USA 93(8):3653–3657
Seki T, Seki M, Onodera R, Katada T, Enomoto T (1998) Cloning of cDNA encoding a novel mouse DNA topoisomerase III (Topo IIIbeta) possessing negatively supercoiled DNA relaxing activity, whose message is highly expressed in the testis. J Biol Chem 273(44):28553–28556
Wang JC (2002) Cellular roles of DNA topoisomerases: a molecular perspective. Nat Rev Mol Cell Biol 3(6):430–440. doi:10.1038/nrm831
Pommier Y, Sun Y, Huang SN, Nitiss JL (2016) Roles of eukaryotic topoisomerases in transcription, replication and genomic stability. Nat Rev Mol Cell Biol 17(11):703–721. doi:10.1038/nrm.2016.111
Vos SM, Tretter EM, Schmidt BH, Berger JM (2011) All tangled up: how cells direct, manage and exploit topoisomerase function. Nat Rev Mol Cell Biol 12(12):827–841. doi:10.1038/nrm3228
Leppard JB, Champoux JJ (2005) Human DNA topoisomerase I: relaxation, roles, and damage control. Chromosoma 114(2):75–85. doi:10.1007/s00412-005-0345-5
Chen SH, Chan NL, Hsieh TS (2013) New mechanistic and functional insights into DNA topoisomerases. Annu Rev Biochem 82:139–170. doi:10.1146/annurev-biochem-061809-100002
Pommier Y (2006) Topoisomerase I inhibitors: camptothecins and beyond. Nat Rev Cancer 6(10):789–802. doi:10.1038/nrc1977
Pommier Y (2013) Drugging topoisomerases: lessons and challenges. ACS Chem Biol 8(1):82–95. doi:10.1021/cb300648v
Hande KR (1998) Etoposide: four decades of development of a topoisomerase II inhibitor. Eur J Cancer 34(10):1514–1521
Nitiss JL (2009) Targeting DNA topoisomerase II in cancer chemotherapy. Nat Rev Cancer 9(5):338–350. doi:10.1038/nrc2607
Tse-Dinh YC (2016) Targeting bacterial topoisomerases: how to counter mechanisms of resistance. Future Med Chem 8(10):1085–1100. doi:10.4155/fmc-2016-0042
Aldred KJ, Kerns RJ, Osheroff N (2014) Mechanism of quinolone action and resistance. Biochemistry 53(10):1565–1574. doi:10.1021/bi5000564
Hsiang YH, Hertzberg R, Hecht S, Liu LF (1985) Camptothecin induces protein-linked DNA breaks via mammalian DNA topoisomerase I. J Biol Chem 260(27):14873–14878
Li TK, Liu LF (2001) Tumor cell death induced by topoisomerase-targeting drugs. Annu Rev Pharmacol Toxicol 41:53–77. doi:10.1146/annurev.pharmtox.41.1.53
Pommier Y, Schwartz RE, Kohn KW, Zwelling LA (1984) Formation and rejoining of deoxyribonucleic acid double-strand breaks induced in isolated cell nuclei by antineoplastic intercalating agents. Biochemistry 23(14):3194–3201
Tewey KM, Chen GL, Nelson EM, Liu LF (1984) Intercalative antitumor drugs interfere with the breakage-reunion reaction of mammalian DNA topoisomerase II. J Biol Chem 259(14):9182–9187
Zwelling LA, Michaels S, Erickson LC, Ungerleider RS, Nichols M, Kohn KW (1981) Protein-associated deoxyribonucleic acid strand breaks in L1210 cells treated with the deoxyribonucleic acid intercalating agents 4′-(9-acridinylamino) methanesulfon-m-anisidide and adriamycin. Biochemistry 20(23):6553–6563
Hsiang YH, Lihou MG, Liu LF (1989) Arrest of replication forks by drug-stabilized topoisomerase I-DNA cleavable complexes as a mechanism of cell killing by camptothecin. Cancer Res 49(18):5077–5082
Champoux JJ (2001) DNA topoisomerases: structure, function, and mechanism. Annu Rev Biochem 70:369–413. doi:10.1146/annurev.biochem.70.1.369
Robert T, Vrielynck N, Mezard C, de Massy B, Grelon M (2016) A new light on the meiotic DSB catalytic complex. Semin Cell Dev Biol 54:165–176. doi:10.1016/j.semcdb.2016.02.025
Redinbo MR, Champoux JJ, Hol WG (2000) Novel insights into catalytic mechanism from a crystal structure of human topoisomerase I in complex with DNA. Biochemistry 39(23):6832–6840
Villa H, Otero Marcos AR, Reguera RM, Balana-Fouce R, Garcia-Estrada C, Perez-Pertejo Y, Tekwani BL, Myler PJ, Stuart KD, Bjornsti MA, Ordonez D (2003) A novel active DNA topoisomerase I in Leishmania donovani. J Biol Chem 278(6):3521–3526. doi:10.1074/jbc.M203991200
Vlachakis D, Pavlopoulou A, Roubelakis MG, Feidakis C, Anagnou NP, Kossida S (2014) 3D molecular modeling and evolutionary study of the Trypanosoma brucei DNA Topoisomerase IB, as a new emerging pharmacological target. Genomics 103(1):107–113. doi:10.1016/j.ygeno.2013.11.008
Zhang H, Meng LH, Zimonjic DB, Popescu NC, Pommier Y (2004) Thirteen-exon-motif signature for vertebrate nuclear and mitochondrial type IB topoisomerases. Nucleic Acids Res 32(7):2087–2092. doi:10.1093/nar/gkh525
Adams DJ, Morgan LR (2011) Tumor physiology and charge dynamics of anticancer drugs: implications for camptothecin-based drug development. Curr Med Chem 18(9):1367–1372
Wall ME, Wani MC, Cook CE, Palmer KH, McPhail AT, Sim GA (1966) Plant antitumor agents. I. The isolation and structure of camptothecin, a novel alkaloidal leukemia and tumor inhibitor from camptotheca acuminata1,2. J Am Chem Soc 88(16):3888–3890. doi:10.1021/ja00968a057
Croce AC, Bottiroli G, Supino R, Favini E, Zuco V, Zunino F (2004) Subcellular localization of the camptothecin analogues, topotecan and gimatecan. Biochem Pharmacol 67(6):1035–1045. doi:10.1016/j.bcp.2003.10.034
de la Loza MC, Wellinger RE (2009) A novel approach for organelle-specific DNA damage targeting reveals different susceptibility of mitochondrial DNA to the anticancer drugs camptothecin and topotecan. Nucleic Acids Res 37(4):e26. doi:10.1093/nar/gkn1087
Wang Y, Lyu YL, Wang JC (2002) Dual localization of human DNA topoisomerase IIIalpha to mitochondria and nucleus. Proc Natl Acad Sci USA 99(19):12114–12119. doi:10.1073/pnas.192449499
Swuec P, Costa A (2014) Molecular mechanism of double Holliday junction dissolution. Cell Biosci 4:36. doi:10.1186/2045-3701-4-36
Chaudhury I, Sareen A, Raghunandan M, Sobeck A (2013) FANCD2 regulates BLM complex functions independently of FANCI to promote replication fork recovery. Nucleic Acids Res 41(13):6444–6459. doi:10.1093/nar/gkt348
Nott A, Tsai LH (2013) The Top3beta way to untangle RNA. Nat Neurosci 16(9):1163–1164. doi:10.1038/nn.3506
Champoux JJ (2002) A first view of the structure of a type IA topoisomerase with bound DNA. Trends Pharmacol Sci 23(5):199–201
Redinbo MR, Stewart L, Kuhn P, Champoux JJ, Hol WG (1998) Crystal structures of human topoisomerase I in covalent and noncovalent complexes with DNA. Science 279(5356):1504–1513
Stewart L, Redinbo MR, Qiu X, Hol WG, Champoux JJ (1998) A model for the mechanism of human topoisomerase I. Science 279(5356):1534–1541
Stewart L, Ireton GC, Champoux JJ (1997) Reconstitution of human topoisomerase I by fragment complementation. J Mol Biol 269(3):355–372. doi:10.1006/jmbi.1997.1056
Fortune JM, Osheroff N (2000) Topoisomerase II as a target for anticancer drugs: when enzymes stop being nice. Prog Nucleic Acid Res Mol Biol 64:221–253
McClendon AK, Osheroff N (2007) DNA topoisomerase II, genotoxicity, and cancer. Mutat Res 623(1–2):83–97. doi:10.1016/j.mrfmmm.2007.06.009
Berger JM, Gamblin SJ, Harrison SC, Wang JC (1996) Structure and mechanism of DNA topoisomerase II. Nature 379(6562):225–232. doi:10.1038/379225a0
Wang JC (1998) Moving one DNA double helix through another by a type II DNA topoisomerase: the story of a simple molecular machine. Q Rev Biophys 31(2):107–144
Wendorff TJ, Schmidt BH, Heslop P, Austin CA, Berger JM (2012) The structure of DNA-bound human topoisomerase II alpha: conformational mechanisms for coordinating inter-subunit interactions with DNA cleavage. J Mol Biol 424(3–4):109–124. doi:10.1016/j.jmb.2012.07.014
Wu CC, Li TK, Farh L, Lin LY, Lin TS, Yu YJ, Yen TJ, Chiang CW, Chan NL (2011) Structural basis of type II topoisomerase inhibition by the anticancer drug etoposide. Science 333(6041):459–462. doi:10.1126/science.1204117
Wei H, Ruthenburg AJ, Bechis SK, Verdine GL (2005) Nucleotide-dependent domain movement in the ATPase domain of a human type IIA DNA topoisomerase. J Biol Chem 280(44):37041–37047. doi:10.1074/jbc.M506520200
Schmidt BH, Osheroff N, Berger JM (2012) Structure of a topoisomerase II-DNA-nucleotide complex reveals a new control mechanism for ATPase activity. Nat Struct Mol Biol 19(11):1147–1154. doi:10.1038/nsmb.2388
Schoeffler AJ, Berger JM (2005) Recent advances in understanding structure-function relationships in the type II topoisomerase mechanism. Biochem Soc Trans 33(Pt 6):1465–1470. doi:10.1042/BST20051465
Roca J, Wang JC (1994) DNA transport by a type II DNA topoisomerase: evidence in favor of a two-gate mechanism. Cell 77(4):609–616
Aravind L, Leipe DD, Koonin EV (1998) Toprim–a conserved catalytic domain in type IA and II topoisomerases, DnaG-type primases, OLD family nucleases and RecR proteins. Nucleic Acids Res 26(18):4205–4213
Schmidt BH, Burgin AB, Deweese JE, Osheroff N, Berger JM (2010) A novel and unified two-metal mechanism for DNA cleavage by type II and IA topoisomerases. Nature 465(7298):641–644. doi:10.1038/nature08974
Pommier Y, Marchand C (2005) Interfacial inhibitors of protein-nucleic acid interactions. Curr Med Chem Anticancer Agents 5(4):421–429
Pommier Y, Kiselev E, Marchand C (2015) Interfacial inhibitors. Bioorg Med Chem Lett 25(18):3961–3965. doi:10.1016/j.bmcl.2015.07.032
Bjornsti MA, Benedetti P, Viglianti GA, Wang JC (1989) Expression of human DNA topoisomerase I in yeast cells lacking yeast DNA topoisomerase I: restoration of sensitivity of the cells to the antitumor drug camptothecin. Cancer Res 49(22):6318–6323
Nitiss J, Wang JC (1988) DNA topoisomerase-targeting antitumor drugs can be studied in yeast. Proc Natl Acad Sci USA 85(20):7501–7505
Wall ME, Wani MC (1995) Camptothecin and taxol: discovery to clinic–thirteenth Bruce F. Cain Memorial Award Lecture. Cancer Res 55(4):753–760
Wall ME, Wani MC (1996) Camptothecin and taxol: from discovery to clinic. J Ethnopharmacol 51(1–3):239–253 (discussion 253–234)
Basili S, Moro S (2009) Novel camptothecin derivatives as topoisomerase I inhibitors. Expert Opin Ther Pat 19(5):555–574. doi:10.1517/13543770902773437
Koster DA, Palle K, Bot ES, Bjornsti MA, Dekker NH (2007) Antitumour drugs impede DNA uncoiling by topoisomerase I. Nature 448(7150):213–217. doi:10.1038/nature05938
Lavergne O, Demarquay D, Kasprzyk PG, Bigg DC (2000) Homocamptothecins: E-ring modified CPT analogues. Ann N Y Acad Sci 922:100–111
Zunino F, Dallavalleb S, Laccabuea D, Berettaa G, Merlinib L, Pratesi G (2002) Current status and perspectives in the development of camptothecins. Curr Pharm Des 8(27):2505–2520
Adams DJ, Wahl ML, Flowers JL, Sen B, Colvin M, Dewhirst MW, Manikumar G, Wani MC (2006) Camptothecin analogs with enhanced activity against human breast cancer cells. II. Impact of the tumor pH gradient. Cancer Chemother Pharmacol 57(2):145–154. doi:10.1007/s00280-005-0008-5
Burris HA, Rothenberg ML, Kuhn JG, Von Hoff DD (1992) Clinical trials with the topoisomerase I inhibitors. Semin Oncol 19(6):663–669
Swami U, Goel S, Mani S (2013) Therapeutic targeting of CPT-11 induced diarrhea: a case for prophylaxis. Curr Drug Targets 14(7):777–797
Dallavalle S, Ferrari A, Biasotti B, Merlini L, Penco S, Gallo G, Marzi M, Tinti MO, Martinelli R, Pisano C, Carminati P, Carenini N, Beretta G, Perego P, De Cesare M, Pratesi G, Zunino F (2001) Novel 7-oxyiminomethyl derivatives of camptothecin with potent in vitro and in vivo antitumor activity. J Med Chem 44(20):3264–3274
Petrangolini G, Pratesi G, De Cesare M, Supino R, Pisano C, Marcellini M, Giordano V, Laccabue D, Lanzi C, Zunino F (2003) Antiangiogenic effects of the novel camptothecin ST1481 (gimatecan) in human tumor xenografts. Mol Cancer Res 1(12):863–870
Bom D, Curran DP, Kruszewski S, Zimmer SG, Thompson Strode J, Kohlhagen G, Du W, Chavan AJ, Fraley KA, Bingcang AL, Latus LJ, Pommier Y, Burke TG (2000) The novel silatecan 7-tert-butyldimethylsilyl-10-hydroxycamptothecin displays high lipophilicity, improved human blood stability, and potent anticancer activity. J Med Chem 43(21):3970–3980
Boven E, Van Hattum AH, Hoogsteen I, Schluper HM, Pinedo HM (2000) New analogues of camptothecins. Activity and resistance. Ann N Y Acad Sci 922:175–177
Van Hattum AH, Schluper HM, Hausheer FH, Pinedo HM, Boven E (2002) Novel camptothecin derivative BNP1350 in experimental human ovarian cancer: determination of efficacy and possible mechanisms of resistance. Int J Cancer 100(1):22–29. doi:10.1002/ijc.10434
Pommier Y, Cushman M (2009) The indenoisoquinoline noncamptothecin topoisomerase I inhibitors: update and perspectives. Mol Cancer Ther 8(5):1008–1014. doi:10.1158/1535-7163.MCT-08-0706
Kummar S, Chen A, Gutierrez M, Pfister TD, Wang L, Redon C, Bonner WM, Yutzy W, Zhang Y, Kinders RJ, Ji J, Allen D, Covey JM, Eiseman JL, Holleran JL, Beumer JH, Rubinstein L, Collins J, Tomaszewski J, Parchment R, Pommier Y, Doroshow JH (2016) Clinical and pharmacologic evaluation of two dosing schedules of indotecan (LMP400), a novel indenoisoquinoline, in patients with advanced solid tumors. Cancer Chemother Pharmacol 78(1):73–81. doi:10.1007/s00280-016-2998-6
Antony S, Agama KK, Miao ZH, Takagi K, Wright MH, Robles AI, Varticovski L, Nagarajan M, Morrell A, Cushman M, Pommier Y (2007) Novel indenoisoquinolines NSC 725776 and NSC 724998 produce persistent topoisomerase I cleavage complexes and overcome multidrug resistance. Cancer Res 67(21):10397–10405. doi:10.1158/0008-5472.CAN-07-0938
Baldwin EL, Osheroff N (2005) Etoposide, topoisomerase II and cancer. Curr Med Chem Anticancer Agents 5(4):363–372
Vogelzang NJ, Raghavan D, Kennedy BJ (1982) VP-16-213 (etoposide): the mandrake root from Issyk-Kul. Am J Med 72(1):136–144
Ross W, Rowe T, Glisson B, Yalowich J, Liu L (1984) Role of topoisomerase II in mediating epipodophyllotoxin-induced DNA cleavage. Cancer Res 44(12 Pt 1):5857–5860
Lee K-H, Xiao Z (2011) Podophyllotoxins and analogs. In: Anticancer agents from natural products, Second Edition. CRC Press, pp 95–122. doi:10.1201/b11185-6
Zhang S, Liu X, Bawa-Khalfe T, Lu LS, Lyu YL, Liu LF, Yeh ET (2012) Identification of the molecular basis of doxorubicin-induced cardiotoxicity. Nat Med 18(11):1639–1642. doi:10.1038/nm.2919
Khiati S, Dalla Rosa I, Sourbier C, Ma X, Rao VA, Neckers LM, Zhang H, Pommier Y (2014) Mitochondrial topoisomerase I (top1mt) is a novel limiting factor of doxorubicin cardiotoxicity. Clin Cancer Res 20(18):4873–4881. doi:10.1158/1078-0432.CCR-13-3373
Douarre C, Sourbier C, Dalla Rosa I, Brata Das B, Redon CE, Zhang H, Neckers L, Pommier Y (2012) Mitochondrial topoisomerase I is critical for mitochondrial integrity and cellular energy metabolism. PLoS ONE 7(7):e41094. doi:10.1371/journal.pone.0041094
Faulds D, Balfour JA, Chrisp P, Langtry HD (1991) Mitoxantrone. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in the chemotherapy of cancer. Drugs 41(3):400–449
Parker BS, Cullinane C, Phillips DR (1999) Formation of DNA adducts by formaldehyde-activated mitoxantrone. Nucleic Acids Res 27(14):2918–2923
Boland MP, Fitzgerald KA, O’Neill LA (2000) Topoisomerase II is required for mitoxantrone to signal nuclear factor kappa B activation in HL60 cells. J Biol Chem 275(33):25231–25238
Larsen AK, Escargueil AE, Skladanowski A (2003) Catalytic topoisomerase II inhibitors in cancer therapy. Pharmacol Ther 99(2):167–181
Erlichman C, Boerner SA, Hallgren CG, Spieker R, Wang XY, James CD, Scheffer GL, Maliepaard M, Ross DD, Bible KC, Kaufmann SH (2001) The HER tyrosine kinase inhibitor CI1033 enhances cytotoxicity of 7-ethyl-10-hydroxycamptothecin and topotecan by inhibiting breast cancer resistance protein-mediated drug efflux. Cancer Res 61(2):739–748
Stewart CF, Leggas M, Schuetz JD, Panetta JC, Cheshire PJ, Peterson J, Daw N, Jenkins JJ 3rd, Gilbertson R, Germain GS, Harwood FC, Houghton PJ (2004) Gefitinib enhances the antitumor activity and oral bioavailability of irinotecan in mice. Cancer Res 64(20):7491–7499. doi:10.1158/0008-5472.CAN-04-0096
Pommier Y, Huang SY, Gao R, Das BB, Murai J, Marchand C (2014) Tyrosyl-DNA-phosphodiesterases (TDP1 and TDP2). DNA Repair (Amst) 19:114–129. doi:10.1016/j.dnarep.2014.03.020
Santi DV, Schneider EL, Ashley GW (2014) Macromolecular prodrug that provides the irinotecan (CPT-11) active-metabolite SN-38 with ultralong half-life, low C(max), and low glucuronide formation. J Med Chem 57(6):2303–2314. doi:10.1021/jm401644v
Staker BL, Hjerrild K, Feese MD, Behnke CA, Burgin AB Jr, Stewart L (2002) The mechanism of topoisomerase I poisoning by a camptothecin analog. Proc Natl Acad Sci USA 99(24):15387–15392. doi:10.1073/pnas.242259599
Acknowledgements
We would like to thank the past and current Bjornsti and van Waardenburg lab members, and colleagues for inspiring discussions that contribute to the continued development of the DNA topoisomerases field. Our apologies to colleagues whose work we did not mention, due to space limitations. RCAMvW greatly appreciates the financial support from the Department of Pharmacology and Toxicology, UAB ACS-IRG Junior Faculty Development Grant (ACS-IRG-60-001-53), the UAB Comprehensive Cancer Center Faculty Development Grant, and DOD OCRP pilot award W81XWH-15-1-0198. M-AB acknowledges the support from the National Institutes of Health and, along with RCAMvW, support from the Alabama Drug Discovery Alliance and the Cancer Center Core Support Grant P30CA013148.
Funding
This study was in part funded by American Cancer Society UAB ACS-IRG Junior Faculty Development Grant (ACS-IRG-60-001-53), Department of Defense OCRP pilot award W81XWH-15-1-0198 to RCAMvW, and the National Institutes of Health Cancer Center Core Support Grant (P30CA013148) to RCAMvW and M-AB.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no conflict of interest.
Ethical approval
This article does not contain any studies with human participants or animals performed by any of the authors.
Rights and permissions
About this article
Cite this article
Cuya, S.M., Bjornsti, MA. & van Waardenburg, R.C. DNA topoisomerase-targeting chemotherapeutics: what’s new?. Cancer Chemother Pharmacol 80, 1–14 (2017). https://doi.org/10.1007/s00280-017-3334-5
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00280-017-3334-5