The anticancer effect of mebendazole may be due to M1 monocyte/macrophage activation via ERK1/2 and TLR8-dependent inflammasome activation

Immunopharmacol Immunotoxicol. 2017 Aug;39(4):199-210. doi: 10.1080/08923973.2017.1320671. Epub 2017 May 4.


Mebendazole (MBZ), a drug commonly used for helminitic infections, has recently gained substantial attention as a repositioning candidate for cancer treatment. However, the mechanism of action behind its anticancer activity remains unclear. To address this problem, we took advantage of the curated MBZ-induced gene expression signatures in the LINCS Connectivity Map (CMap) database. The analysis revealed strong negative correlation with MEK/ERK1/2 inhibitors. Moreover, several of the most upregulated genes in response to MBZ exposure were related to monocyte/macrophage activation. The MBZ-induced gene expression signature in the promyeloblastic HL-60 cell line was strongly enriched in genes involved in monocyte/macrophage pro-inflammatory (M1) activation. This was subsequently validated using MBZ-treated THP-1 monocytoid cells that demonstrated gene expression, surface markers and cytokine release characteristic of the M1 phenotype. At high concentrations MBZ substantially induced the release of IL-1β and this was further potentiated by lipopolysaccharide (LPS). At low MBZ concentrations, cotreatment with LPS was required for MBZ-stimulated IL-1β secretion to occur. Furthermore, we show that the activation of protein kinase C, ERK1/2 and NF-kappaB were required for MBZ-induced IL-1β release. MBZ-induced IL-1β release was found to be dependent on NLRP3 inflammasome activation and to involve TLR8 stimulation. Finally, MBZ induced tumor-suppressive effects in a coculture model with differentiated THP-1 macrophages and HT29 colon cancer cells. In summary, we report that MBZ induced a pro-inflammatory (M1) phenotype of monocytoid cells, which may, at least partly, explain MBZ's anticancer activity observed in animal tumor models and in the clinic.

Keywords: Repositioning; cancer therapy; macrophages; mebendazole; monocytes.

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Cell Line
  • Cell Line, Tumor
  • Gene Expression / drug effects
  • HEK293 Cells
  • HL-60 Cells
  • HT29 Cells
  • Humans
  • Inflammasomes / drug effects*
  • Inflammasomes / metabolism
  • Interleukin-1beta / metabolism
  • Lipopolysaccharides / pharmacology
  • MAP Kinase Signaling System / drug effects*
  • Macrophage Activation / drug effects*
  • Macrophages / drug effects
  • Macrophages / metabolism
  • Mebendazole / pharmacology*
  • Monocytes / drug effects*
  • Monocytes / metabolism
  • NF-kappa B / metabolism
  • Toll-Like Receptor 8 / metabolism*
  • Up-Regulation / drug effects


  • Antineoplastic Agents
  • Inflammasomes
  • Interleukin-1beta
  • Lipopolysaccharides
  • NF-kappa B
  • TLR8 protein, human
  • Toll-Like Receptor 8
  • Mebendazole