Catalog Number: 3544
Chemical Name: 2-(4-Morpholinyl)-6-(1-thianthrenyl)-4H-pyran-4-one
Biological Activity
Potent, selective and competitive ATM kinase inhibitor (Ki = 2.2 nM, IC50 values are 13, 2500, 9300, 16600, > 100000 and > 100000 nM at ATM, DNA-PK, mTOR, PI 3-kinase, PI 4-K and ATR respectively). Decreases viability of MCF-7, A549 and HCT116 cells and decreases p21CIP1 levels in vitro. Acts as a radio- and chemosensitizer for the treatment of cancer.
Technical Data
  • M.Wt:
  • Formula:
  • Solubility:
    Soluble to 100 mM in DMSO and to 50 mM in ethanol
  • Purity:
  • Storage:
    Desiccate at -20°C
  • CAS No:
The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis. All Tocris products are intended for laboratory research use only.
Background References
  1. Identification and characterization of a novel and specific inhibitor of the ataxia-telangiectasia mutated kinase ATM.
    Hickson I, Zhao Y, Richardson CJ et al.
    Cancer Res
  2. Ataxia telangiectasia mutated and p21CIP1 modulate cell survival of drug-induced senescent tumor cells: Implications for chemotherapy.
    Crescenzi et al.
    Clin.Cancer Res., 2008;14:1877
  3. Ataxia-telangiectasia mutated kinase regulates ribonucleotide reductase and mitochondrial homeostasis.
    Eaton et al.
    J.Clin.Invest., 2007;117:2723

The citations listed below are publications that use Tocris products. Selected citations for KU 55933 include:

37 Citations: Showing 1 - 10
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  1. Activation of DNA Damage Response Pathways during Lytic Replication of KSHV.
    Authors: Hollingworth Et al.
    Mol Cell Biol 2015;7:2908
  2. A radiosensitivity MiRNA signature validated by the TCGA database for head and neck squamous cell carcinomas.
    Authors: Liu Et al.
    Aging Cell 2015;6:34649
  3. Cellular responses to a prolonged delay in mitosis are determined by a DNA damage response controlled by Bcl-2 family proteins.
    Authors: Colin Et al.
    Viruses 2015;5:140156
  4. The E3 ubiquitin ligase ARIH1 protects against genotoxic stress by initiating a 4EHP-mediated mRNA translation arrest.
    Authors: Stechow Et al.
    Proc Natl Acad Sci U S A 2015;35:1254
  5. Lamin A/C-dependent interaction with 53BP1 promotes cellular responses to DNA damage.
    Authors: Gibbs-Seymour Et al.
    Open Biol 2015;14:162
  6. Pharmacologic inhibition of ATR and ATM offers clinically important distinctions to enhancing platinum or radiation response in ovarian, endometrial, and cervical cancer cells.
    Authors: Teng Et al.
    Gynecol Oncol 2015;136:554
  7. F-box protein FBXO31 directs degradation of MDM2 to facilitate p53-mediated growth arrest following genotoxic stress.
    Authors: Malonia Et al.
    J Cell Biol 2015;112:8632
  8. Contrasting Effects of the Cytotoxic Anticancer Drug Gemcitabine and the EGFR Tyrosine Kinase Inhibitor Gefitinib on NK Cell-Mediated Cytotoxicity via Regulation of NKG2D Ligand in Non-Small-Cell Lung Cancer Cells.
    Authors: Okita Et al.
    PLoS One 2015;10:e0139809
  9. TLR8 signaling enhances tumor immunity by preventing tumor-induced T-cell senescence.
    Authors: Ye Et al.
    EMBO Mol Med 2014;6:1294
  10. SMAR1 coordinates HDAC6-induced deacetylation of Ku70 and dictates cell fate upon irradiation.
    Authors: Chaudhary Et al.
    Cell Death Dis 2014;5:e1447
  11. ATM specifically mediates repair of double-strand breaks with blocked DNA ends.
    Authors: Alvarez-Quilón Et al.
    Nat Commun 2014;5:3347
  12. The scaffold protein WRAP53β orchestrates the ubiquitin response critical for DNA double-strand break repair.
    Authors: Henriksson Et al.
    Genes Dev 2014;28:2726
  13. Preconditioning stimuli induce autophagy via sphingosine kinase 2 in mouse cortical neurons.
    Authors: Sheng Et al.
    Oncotarget 2014;289:20845
  14. Human papillomavirus episome stability is reduced by aphidicolin and controlled by DNA damage response pathways.
    Authors: Edwards Et al.
    J Virol 2013;87:3979
  15. ATP-competitive mTOR kinase inhibitors delay plant growth by triggering early differentiation of meristematic cells but no developmental patterning change.
    Authors: Montané and Menand
    Nat Chem Biol 2013;64:4361
  16. Senataxin, defective in the neurodegenerative disorder ataxia with oculomotor apraxia 2, lies at the interface of transcription and the DNA damage response.
    Authors: Yüce and West
    Mol Cell Biol 2013;33:406
  17. Functional intersection of ATM and DNA-dependent protein kinase catalytic subunit in coding end joining during V(D)J recombination.
    Authors: Lee Et al.
    PLoS One 2013;33:3568
  18. Mechanism of DNA resection during intrachromosomal recombination and immunoglobulin class switching.
    Authors: Bothmer Et al.
    Chembiochem 2013;210:115
  19. Hairpin-end conformation of adeno-associated virus genome determines interactions with DNA-repair pathways.
    Authors: Cataldi and McCarty
    J Biol Chem 2013;20:686
  20. A new method for high-resolution imaging of Ku foci to decipher mechanisms of DNA double-strand break repair.
    Authors: Britton Et al.
    J Cell Biol 2013;202:579
  21. The heterogenic final cell cycle of chicken retinal Lim1 horizontal cells is not regulated by the DNA damage response pathway.
    Authors: Fard Et al.
    Cell Cycle 2013;13:408
  22. Functional redundancy between the XLF and DNA-PKcs DNA repair factors in V(D)J recombination and nonhomologous DNA end joining.
    Authors: Oksenych Et al.
    J Biol Chem 2013;110:2234
  23. Role of 53BP1 oligomerization in regulating double-strand break repair.
    Authors: Lottersberger Et al.
    Proc Natl Acad Sci U S A 2013;110:2146
  24. ATM and MET kinases are synthetic lethal with nongenotoxic activation of p53.
    Authors: Sullivan Et al.
    Proc Natl Acad Sci U S A 2012;8:646
  25. Mechanism-based screen establishes signalling framework for DNA damage-associated G1 checkpoint response.
    Authors: Richardson Et al.
    PLoS One 2012;7:e31627
  26. SPOC1 modulates DNA repair by regulating key determinants of chromatin compaction and DNA damage response.
    Authors: Mund Et al.
    Nucleic Acids Res 2012;40:11363
  27. Regulation of SIRT1 activity by genotoxic stress.
    Authors: Yuan Et al.
    Genes Dev 2012;26:791
  28. Kinase-dead ATM protein causes genomic instability and early embryonic lethality in mice.
    Authors: Yamamoto Et al.
    J Virol 2012;198:305
  29. Telomeric DNA damage is irreparable and causes persistent DNA-damage-response activation.
    Authors: Fumagalli Et al.
    Nat Cell Biol 2012;14:355
  30. Detection of early Abl kinase activation after ionizing radiation by using a peptide biosensor.
    Authors: Tang Et al.
    Mol Cell Biol 2012;13:665
  31. Re-replication induced by geminin depletion occurs from G2 and is enhanced by checkpoint activation.
    Authors: Klotz-Noack Et al.
    J Cell Sci 2012;125:2436
  32. γ-Radiation promotes immunological recognition of cancer cells through increased expression of cancer-testis antigens in vitro and in vivo.
    Authors: Sharma Et al.
    Gene Ther 2011;6:e28217
  33. The phenotypic radiation resistance of CD44+/CD24(-or low) breast cancer cells is mediated through the enhanced activation of ATM signaling.
    Authors: Yin and Glass
    PLoS One 2011;6:e24080
  34. Differential inhibitor sensitivity between human kinases VRK1 and VRK2.
    Authors: Vázquez-Cedeira Et al.
    PLoS One 2011;6:e23235
  35. Identification of small molecule inhibitors of phosphatidylinositol 3-kinase and autophagy.
    Authors: Farkas Et al.
    J Biol Chem 2011;286:38904
  36. Differential effects of DNA double-strand break repair pathways on single-strand and self-complementary adeno-associated virus vector genomes.
    Authors: Cataldi and McCarty
    J Exp Med 2010;84:8673
  37. Selenium compounds activate ATM-dependent DNA damage response via the mismatch repair protein hMLH1 in colorectal cancer cells.
    Authors: Qi Et al.
    Am J Physiol Cell Physiol 2010;285:33010
Expand to show all 37 Citations

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