The antihelmintic flubendazole inhibits microtubule function through a mechanism distinct from Vinca alkaloids and displays preclinical activity in leukemia and myeloma

Blood. 2010 Jun 10;115(23):4824-33. doi: 10.1182/blood-2009-09-243055. Epub 2010 Mar 26.


On-patent and off-patent drugs with previously unrecognized anticancer activity could be rapidly repurposed for this new indication given their prior toxicity testing. To identify such compounds, we conducted chemical screens and identified the antihelmintic flubendazole. Flubendazole induced cell death in leukemia and myeloma cell lines and primary patient samples at nanomolar concentrations. Moreover, it delayed tumor growth in leukemia and myeloma xenografts without evidence of toxicity. Mechanistically, flubendazole inhibited tubulin polymerization by binding tubulin at a site distinct from vinblastine. In addition, cells resistant to vinblastine because of overexpression of P-glycoprotein remained fully sensitive to flubendazole, indicating that flubendazole can overcome some forms of vinblastine resistance. Given the different mechanisms of action, we evaluated the combination of flubendazole and vinblastine in vitro and in vivo. Flubendazole synergized with vinblastine to reduce the viability of OCI-AML2 cells. In addition, combinations of flubendazole with vinblastine or vincristine in a leukemia xenograft model delayed tumor growth more than either drug alone. Therefore, flubendazole is a novel microtubule inhibitor that displays preclinical activity in leukemia and myeloma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antinematodal Agents / agonists
  • Antinematodal Agents / pharmacology*
  • Antinematodal Agents / therapeutic use
  • Antineoplastic Agents, Phytogenic / agonists
  • Antineoplastic Agents, Phytogenic / pharmacology
  • Antineoplastic Agents, Phytogenic / therapeutic use
  • Cell Death
  • Cell Survival
  • Dose-Response Relationship, Drug
  • Drug Synergism
  • Female
  • HeLa Cells
  • Humans
  • Leukemia / drug therapy*
  • Leukemia / metabolism
  • Male
  • Mebendazole / agonists
  • Mebendazole / analogs & derivatives*
  • Mebendazole / pharmacology
  • Mebendazole / therapeutic use
  • Mice
  • Microtubules / metabolism*
  • Multiple Myeloma / drug therapy*
  • Multiple Myeloma / metabolism
  • U937 Cells
  • Vinblastine / agonists
  • Vinblastine / pharmacology
  • Vinblastine / therapeutic use
  • Vinca Alkaloids / pharmacology*
  • Xenograft Model Antitumor Assays / methods


  • Antinematodal Agents
  • Antineoplastic Agents, Phytogenic
  • Vinca Alkaloids
  • Vinblastine
  • Mebendazole
  • flubendazole