Activation of nuclear factor-kappa B (NFκB) in prostate cancer is mediated by PKC epsilon (PKC{epsilon}) - Abstract

Protein kinase C ε (PKCε) has emerged as an oncogenic kinase and plays important roles in cell survival, mitogenesis and invasion.

PKCε is up-regulated in most epithelial cancers, including prostate, breast, and lung cancer. Here we report that PKCε is an essential mediator of NF-κB activation in prostate cancer cells. A strong correlation exists between PKCε overexpression and NF-κB activation status in prostate cancer cells. Moreover, transgenic overexpression of PKCε in the mouse prostate causes preneoplastic lesions that display significant NF-κB hyperactivation. PKCε RNAi depletion or inhibition in prostate cancer cells diminishes NF-κB translocation to the nucleus with subsequent impairment of both activation of NF-κB transcription and induction of NF-κB responsive genes in response to the proinflammatory cytokine tumor necrosis factor α (TNFα). On the other hand, PKCε overexpression in normal prostate cells enhances activation of the NF-κB pathway. A mechanistic analysis revealed that TNFα activates PKCε via a C1 domain/diacylglycerol-dependent mechanism that involves phosphatidylcholine-phospholipase C. Moreover, PKCε facilitates the assembly of the TNF receptor-I signaling complex to trigger NF-κB activation. Our studies identified a molecular link between PKCε and NF-κB that controls key responses implicated in prostate cancer progression.

Written by:
Garg R, Blando J, Perez CJ, Wang H, Benavides FJ, Kazanietz MG.   Are you the author?
Department of Pharmacology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104.

Reference: J Biol Chem. 2012 Oct 26;287(44):37570-82.
doi: 10.1074/jbc.M112.398925


PubMed Abstract
PMID: 22955280

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