Betulinic acid targets YY1 and ErbB2 through cannabinoid receptor-dependent disruption of microRNA-27a:ZBTB10 in breast cancer

Mol Cancer Ther. 2012 Jul;11(7):1421-31. doi: 10.1158/1535-7163.MCT-12-0026. Epub 2012 May 2.


Treatment of ErbB2-overexpressing BT474 and MDA-MB-453 breast cancer cells with 1 to 10 μmol/L betulinic acid inhibited cell growth, induced apoptosis, downregulated specificity protein (Sp) transcription factors Sp1, Sp3, and Sp4, and decreased expression of ErbB2. Individual or combined knockdown of Sp1, Sp3, Sp4 by RNA interference also decreased expression of ErbB2 and this response was because of repression of YY1, an Sp-regulated gene. Betulinic acid-dependent repression of Sp1, Sp3, Sp4, and Sp-regulated genes was due, in part, to induction of the Sp repressor ZBTB10 and downregulation of microRNA-27a (miR-27a), which constitutively inhibits ZBTB10 expression, and we show for the first time that the effects of betulinic acid on the miR-27a:ZBTB10-Sp transcription factor axis were cannabinoid 1 (CB1) and CB2 receptor-dependent, thus identifying a new cellular target for this anticancer agent.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apoptosis / drug effects
  • Betulinic Acid
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / metabolism*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cricetinae
  • Female
  • Gene Expression Regulation, Neoplastic / drug effects
  • Humans
  • Mice
  • Mice, Nude
  • MicroRNAs / genetics*
  • Pentacyclic Triterpenes
  • Receptor, ErbB-2 / antagonists & inhibitors*
  • Receptors, Cannabinoid / metabolism*
  • Repressor Proteins / genetics*
  • Sp Transcription Factors / genetics
  • Sp Transcription Factors / metabolism
  • Triterpenes / pharmacology*
  • YY1 Transcription Factor / antagonists & inhibitors*


  • Antineoplastic Agents, Phytogenic
  • MIRN27 microRNA, human
  • MicroRNAs
  • Pentacyclic Triterpenes
  • Receptors, Cannabinoid
  • Repressor Proteins
  • Sp Transcription Factors
  • Triterpenes
  • YY1 Transcription Factor
  • ZBTB10 protein, human
  • Receptor, ErbB-2
  • Betulinic Acid