γ-Secretase-dependent cleavage of E-cadherin by staurosporine in breast cancer cells

Cell Commun Adhes. 2012 Feb;19(1):11-6. doi: 10.3109/15419061.2012.665969. Epub 2012 Mar 8.

Abstract

E-cadherin is a transmembrane protein that serves as a cell adhesion molecule component of the adherens junction. We previously showed that cadmium induced γ-secretase-dependent E-cadherin cleavage via oxidative stress. In this study, we report that staurosporine (STS)-induced apoptosis induces caspase-2 and/or -8-dependent E-cadherin cleavage. STS increased γ-secretase-dependent cleavage of E-cadherin in breast cancer cells through caspase activation. The ability of the γ-secretase inhibitor DAPT and the caspase inhibitor zVAD-FMK to block E-cadherin cleavage provided support for these results. The cleavage of E-cadherin was blocked by caspase-2 and -8 inhibitors. Immunofluorescence analysis confirmed that, along with the disappearance of E-cadherin staining at the cell surface, the E-cadherin cytoplasmic domain accumulated in the cytosol. In the presence of an inhibitor of γ-secretase or caspase, the cleavage of E-cadherin was partially blocked. Our findings suggest that activation of caspase-2/-8 stimulated the disruption of cadherin-mediated cell-cell contacts in apoptotic cells via γ-secretase activation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Chloromethyl Ketones / pharmacology
  • Amyloid Precursor Protein Secretases / antagonists & inhibitors
  • Amyloid Precursor Protein Secretases / metabolism*
  • Apoptosis / drug effects*
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / enzymology
  • Breast Neoplasms / metabolism
  • Cadherins / metabolism*
  • Caspase 2 / metabolism
  • Caspase 8 / metabolism
  • Caspase Inhibitors
  • Cell Line, Tumor
  • Enzyme Inhibitors / pharmacology
  • Female
  • Humans
  • Microscopy, Fluorescence
  • Staurosporine / pharmacology*
  • Staurosporine / therapeutic use

Substances

  • Amino Acid Chloromethyl Ketones
  • Cadherins
  • Caspase Inhibitors
  • Enzyme Inhibitors
  • benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone
  • Amyloid Precursor Protein Secretases
  • Caspase 2
  • Caspase 8
  • Staurosporine