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PubMed · 15019843

MAPK signaling pathways modulate IL-1beta expression in human keratinocytes.

Derek V Henley·Clifford J Bellone·Debbie A Williams·Mary F Ruh
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Abstract

The signaling pathways that modulate IL-1beta expression in human keratinocytes have not been well defined. We have previously shown that TCDD-stimulated AhR-dependent IL-1beta expression in human keratinocytes is due to posttranscriptional regulation involving mRNA stabilization. Since TCDD activates a variety of cellular signaling pathways such as PKC, JNK, and ERK, we investigated these pathways to determine their roles in TCDD-stimulated IL-1beta expression in the human keratinocyte cell line SCC-12F. In this study, we used specific signaling inhibitors to show that ERK and JNK, but not transglutaminase, PKC, or p38, signaling modulate IL-1beta expression. In addition, we show that ERK is constitutively active and unaffected by TCDD treatment and differentiation, while the JNK signaling pathway is modulated by TCDD in an AhR-dependent manner. Thus, both the ERK and JNK MAPK pathways are necessary for IL-1beta expression in TCDD-stimulated human keratinocytes, however, they act at different levels to modulate IL-1beta expression.

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Cell Line, TransformedEnzyme ActivationEnzyme InhibitorsHumansInterleukin-1JNK Mitogen-Activated Protein KinasesKeratinocytesMAP Kinase Signaling SystemMitogen-Activated Protein KinasesPolychlorinated DibenzodioxinsProtein Kinase CRNA, MessengerReceptors, Aryl HydrocarbonJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Derek V Henley, Clifford J Bellone, Debbie A Williams, Mary F Ruh. 2004-04-01. MAPK signaling pathways modulate IL-1beta expression in human keratinocytes.. https://doi.org/10.1016/j.abb.2004.02.001

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