Topotecan hydrochloride

Hycamtin, Topotecan lactone
An Antagonist of 5-HT3A and an Agonist of 5-HT3B Receptors
    Cat #: T-160
    Alternative Name Hycamtin, Topotecan lactone
  • Lyophilized Powder
  • Bioassay Tested
  • Source Synthetic
    MW: 457.9
    Purity: 99%
    Effective concentration 10-200 µM.
      • Topotecan hydrochloride
    Chemical name 9-Dimethylaminomethyl-10-hydroxycamptothecin.
    Molecular formula C23H24ClN3O5.
    CAS No.: 119413-54-6.
    PubChem CID 60699
    Activity Topotecan is a 5-HT3A receptor antagonist1.
    Shipping and storage Shipped at room temperature. Product as supplied can be stored intact at room temperature for several weeks. For longer periods, it should be stored at -20°C.
    Solubility 100 mM in DMSO. Centrifuge all product preparations before use (10000 x g 5 min).
    Storage of solutions Up to four weeks at 4°C or three months at -20°C.
      • Topotecan hydrochloride
        Alomone Labs Topotecan hydrochloride blocks 5-HT3A receptors expressed in HEK 293T cells. 
        5-HT3A receptor currents were elicited by 10 µM 5-HT, delivered every 3 minutes. Topotecan hydrochloride (#T-160) was applied 30 seconds before stimulation at 10, 100 and 200 µM as indicated and completely inhibited the 5-HT induced current in a dose dependent and reversible manner.
    References - Scientific background
    • 1. Hannon, J. et al. (2008) Behav. Brain Res. 195, 198.
    • 2. Nakamura, Y. et al. (2013) J. Neurochem. 125, 7.
    • 3. Pang, B. et al. (2015) Nat. Chem. Biol. 11, 472.
      • Serotonin (5-hydroxytryptamine, 5-HT) is a monoamine neurotransmitter synthesized from the amino acid tryptophan by the enzyme tryptophan-decarboxylase. The 5-HT3 channel is a ligand gated ion channel receptor of the cys-loop channel family. It is a pentamer with five subunits surrounding a central channel1.

        Topotecan (Hycamtin) is a synthetic, potent and selective antagonist of the 5-HT3A channel derived from the plant alkaloid Camptothecin. Topotecan has an effective concentration of 10-200 μM and an IC50 of 114.1 μM for the 5-HT3A receptor.

        Interestingly, in addition to its inhibitory effect on 5-HT3 receptors, Topotecan can also potentiate the 5-HT receptor. Topotecan’s dual modulation properties depend on the receptor’s subunit composition. Topotecan causes current enhancement in receptors containing the 5-HT3B subunit through means of increased 5-HT affinity to its receptor or a rise in the receptor associated ion channel’s probability of opening. Thus, Topotecan might be effective in distinguishing between different 5-HT3A and 5-HT3B receptors2.

        In addition to its function as a 5-HT3 antagonist Topotecan is used as an anti-cancer drug in various malignancies. Topotecan’s chemotherapeutic effect is achieved through inhibition of Topoisomerase-1, inducing DNA damage at transcriptionally active genomic areas3.

    Target 5-HT3A/B receptors
    Last update: 21/07/2019

    Topotecan hydrochloride (#T-160) is a highly pure, synthetic, and biologically active compound.

    For research purposes only, not for human use