TNF-α induces expression of urokinase-type plasminogen activator and β-catenin activation through generation of ROS in human breast epithelial cells

Biochem Pharmacol. 2010 Dec 15;80(12):2092-100. doi: 10.1016/j.bcp.2010.08.014. Epub 2010 Sep 9.


Malignant tumors have a capability to degrade the extracellular matrix (ECM) by controlled proteolysis. One of the important components of the proteolysis system involved in such process is urokinase-type plasminogen activator (uPA). Tumor necrosis factor (TNF)-α was found to stimulate uPA. TNF-α impaired the ability of cells to aggregate and to attain compaction. Dyscohesion (cell-cell dissociation) induced by TNF-α was associated with the disordered expression of cadherin/β-catenin at the sites of cell-cell contact. We observed that human breast epithelial (MCF-10A) cells treated with TNF-α transiently up-regulated expression of uPA and its mRNA transcript. In addition, TNF-α induced activation of β-catenin in MCF-10A cells. Based on these findings, we attempted to examine the role of β-catenin and its partner, Tcf-4 in upregulation of uPA. siRNA knock down of β-catenin abrogated TNF-α-induced uPA expression as well as Tcf-4/β-catenin DNA binding. TNF-α-stimulated MCF-10A cells exhibited increased intracellular accumulation of reactive oxygen species (ROS). TNF-α-induced expression of uPA and activation of β-catenin signaling appear to be mediated by ROS in MCF-10A cells, as both events were blocked by the antioxidant N-acetylcysteine. Eupatilin (5,7-dihydroxy-3',4',6-tri-methoxy-flavone), a pharmacologically active flavone derived from Artemisia asiatica, has been shown to possess strong antioxidative activity. Eupatilin inhibited TNF-α-induced intracellular ROS accumulation, expression of uPA and β-catenin activation. Moreover, eupatilin inhibited the TNF-α-induced invasion of MCF-10A cells. Taken together, the above results suggest that eupatilin has chemopreventive effects on mammary tumorigenesis by targeting the β-catenin-uPA axis stimulated by TNF-α.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anticarcinogenic Agents / pharmacology
  • Cell Line
  • Cell Movement
  • Epithelial Cells / drug effects
  • Epithelial Cells / physiology*
  • Flavonoids / pharmacology
  • Humans
  • Mammary Glands, Human / drug effects
  • Mammary Glands, Human / metabolism*
  • Reactive Oxygen Species / metabolism*
  • Signal Transduction
  • Tumor Necrosis Factor-alpha / pharmacology
  • Tumor Necrosis Factor-alpha / physiology*
  • Urokinase-Type Plasminogen Activator / biosynthesis*
  • beta Catenin / metabolism*


  • Anticarcinogenic Agents
  • Flavonoids
  • Reactive Oxygen Species
  • Tumor Necrosis Factor-alpha
  • beta Catenin
  • eupatilin
  • Urokinase-Type Plasminogen Activator