Inhibition of Myb-dependent gene expression by the sesquiterpene lactone mexicanin-I

Leukemia. 2012 Apr;26(4):615-22. doi: 10.1038/leu.2011.275. Epub 2011 Oct 11.


The c-myb proto-oncogene encodes a transcription factor that is highly expressed in the progenitor cells of the hematopoietic system, where it regulates the expression of genes important for lineage determination, cell proliferation and differentiation. There is strong evidence that deregulation of c-myb expression is involved in the development of human tumors, particularly of certain types of leukemia, and breast and colon cancer. The c-Myb protein is therefore an interesting therapeutic target. Here, we have investigated the potential of natural sesquiterpene lactones (STLs), a class of compounds that are active constituents of a variety of medicinal plants, to suppress Myb-dependent gene expression. We have developed a test system that allows screening of compounds for their ability to interfere with the activation of Myb target genes. Using this assay system, we have identified the STL mexicanin-I as the first cell-permeable, low-molecular-weight inhibitor of Myb-induced gene expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetyltransferases / antagonists & inhibitors
  • Animals
  • Cell Line
  • Cell Proliferation / drug effects
  • Chickens
  • Gene Expression Regulation, Neoplastic / drug effects*
  • Humans
  • K562 Cells
  • Lactones / pharmacology*
  • Leukemia, Myeloid, Acute / drug therapy
  • Proto-Oncogene Proteins c-myb / antagonists & inhibitors*
  • Sesquiterpenes / pharmacology*


  • Lactones
  • Proto-Oncogene Proteins c-myb
  • Sesquiterpenes
  • mexicanin
  • parthenolide
  • Acetyltransferases
  • mim-1 protein, Gallus gallus