Antioxidant c-FLIP inhibits fas ligand-induced NF-κB activation in a phosphatidylinositol 3-kinase/Akt-dependent manner

Anand Krishnan V. Iyer*, Neelam Azad, Siera Talbot, Christian Stehlik, Bin Lu, Liying Wang, Yon Rojanasakul

*Corresponding author for this work

Research output: Contribution to journalArticle

28 Scopus citations

Abstract

Fas ligand (FasL) belongs to the TNF family of death ligands, and its binding to the FasR leads to activation of several downstream signaling pathways and proteins, including NF-κB and PI3K/Akt. However, it is not known whether cross-talk exists between NF-κB and PI3K/Akt in the context of FasL signaling. We demonstrate using both human renal epithelial 293T cells and Jurkat T-lymphocyte cells that although FasL activates both Akt and NF-κB, Akt inhibits FasL-dependent NF-κB activity in a reactive oxygen species-dependent manner. Cellular FLICE-inhibitory protein (c-FLIP), an antioxidant and an important component of the death-inducing signaling complex, also represses NF-κB upstream of the regulatory IκB kinase-γ protein subunit in the NF-κB signaling pathway, and positive cross-talk exists between Akt and c-FLIP in the context of inhibition of FasL-induced NF-κB activity. The presence of two death effector domains of c-FLIP and S-nitrosylation of its caspase-like domain were found to be important for mediating c-FLIP-dependent downregulation of NF-κB activity. Taken together, our study reveals a novel link between NF-κB and PI3K/Akt and establishes c-FLIP as an important regulator of FasL-mediated cell death.

Original languageEnglish (US)
Pages (from-to)3256-3266
Number of pages11
JournalJournal of Immunology
Volume187
Issue number6
DOIs
StatePublished - Sep 15 2011

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'Antioxidant c-FLIP inhibits fas ligand-induced NF-κB activation in a phosphatidylinositol 3-kinase/Akt-dependent manner'. Together they form a unique fingerprint.

Cite this