Cytotoxic peptides hemiasterlin, hemiasterlin A and hemiasterlin B induce mitotic arrest and abnormal spindle formation

Cancer Chemother Pharmacol. 1997;39(3):223-6. doi: 10.1007/s002800050564.


Purpose: Hemiasterlin, hemiasterlin A and hemiasterlin B are newly isolated cytotoxic tripeptides with potential as antitumor drugs. We wished to determine their mechanism of cytotoxicity.

Methods: We studied their effect on cell survival, cell cycle progression, and microtubule morphology in MCF-7 human mammary carcinoma cells.

Results: At the nanomolar concentrations at which they were cytotoxic, the peptides induced arrest in mitotic metaphase. Hemiasterlin A produced abnormal mitotic spindles like those produced by the microtubule inhibitors taxol, nocodazole and vinblastine at low concentrations. At high concentrations hemiasterlin A did not cause microtubule bundling like taxol, but caused microtubule depolymerization like nocodazole and vinblastine.

Conclusions: The hemiasterlins probably exert their cytotoxic effect by inhibiting spindle microtubule dynamics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology*
  • Breast Neoplasms / drug therapy
  • Cell Cycle / drug effects*
  • Dimethyl Sulfoxide / pharmacology
  • Drug Screening Assays, Antitumor
  • Female
  • Humans
  • Marine Toxins / pharmacology*
  • Oligopeptides / pharmacology*
  • Porifera / chemistry*
  • Spindle Apparatus / drug effects*
  • Tumor Cells, Cultured / drug effects


  • Antineoplastic Agents
  • Marine Toxins
  • Oligopeptides
  • hemiasterlin A
  • hemiasterlin B
  • Dimethyl Sulfoxide