Induction of EGF-dependent apoptosis by vacuolar-type H+-ATPase inhibitors in A431 cells overexpressing the EGF receptor

Yuya Yoshimoto, Masaya Imoto

Research output: Contribution to journalArticlepeer-review

39 Citations (Scopus)

Abstract

The stimulation of human tumor cells overexpressing epidermal growth factor receptor (EGFR) with EGF enhances tumor development and malignancy. Therefore, compounds that modulate the EGF-mediated signal inducing apoptosis in EGFR-overexpressing cells would represent a new class of antitumor drug and might be useful in the treatment of a subset of human tumors. In the course of screening for compounds that induce apoptosis in EGFR-overexpressing human epidermal carcinoma A431 cells from secondary metabolites of microorganisms, we found that vacuolar-type H+-ATPase (V-ATPase) inhibitors, such as concanamycin B and destruxin E, induced apoptosis only when the cells were stimulated with EGF. The EGF-dependent apoptosis by V-ATPase inhibitors was not observed in other types of human tumor cells which do not overexpress EGFR. The apoptosis in A431 cells was inhibited by anti-FasL antibody which neutralized the cytotoxic effect of FasL, indicating that the Fas/FasL system was involved. The expression of cell surface FasL was upregulated by stimulation with EGF and increased further by V-ATPase inhibitors. Moreover, EGF inhibited cytotoxic Fas antibody-induced apoptosis, whereas V-ATPase inhibitors disrupted the protective effect of EGF on apoptosis in A431 cells. Taken together, these results suggested that V-ATPase inhibitors induced EGF-dependent apoptosis in A431 cells, possibly through both the enhancement of EGF-induced cell surface expression of FasL and the disruption of an EGF-induced survival signal.

Original languageEnglish
Pages (from-to)118-127
Number of pages10
JournalExperimental Cell Research
Volume279
Issue number1
DOIs
Publication statusPublished - 2002 Jan 1

Keywords

  • A431
  • Apoptosis
  • Concanamycin B
  • Destruxin E
  • Epidermal growth factor receptor (EGFR)
  • Fas ligand (FasL)
  • Vacuolar-type H-ATPase (V-ATPase)

ASJC Scopus subject areas

  • Cell Biology

Fingerprint Dive into the research topics of 'Induction of EGF-dependent apoptosis by vacuolar-type H<sup>+</sup>-ATPase inhibitors in A431 cells overexpressing the EGF receptor'. Together they form a unique fingerprint.

Cite this