TY - JOUR
T1 - Aberrant IKKα and IKKβ cooperatively activate NF-κB and induce EGFR/AP1 signaling to promote survival and migration of head and neck cancer
AU - Nottingham, L. K.
AU - Yan, C. H.
AU - Yang, X.
AU - Si, H.
AU - Coupar, J.
AU - Bian, Y.
AU - Cheng, T. F.
AU - Allen, C.
AU - Arun, P.
AU - Gius, D.
AU - Dang, L.
AU - Van Waes, C.
AU - Chen, Z.
N1 - Funding Information:
This project is supported by NIDCD Intramural projects Z01-DC-00016, Z01-DC-00073 and Z01-DC-00074. We thank Dr Michael Karin (UC San Diego) and Dr Ulrich Siebenlist (NIH/NIAID) for kindly providing the IKK plasmids; Dr Neil Perkins (Newcastle University, UK) for kindly providing anti-p-p52 antibody; Dr Jialing Zhang for technical assistance; and Dr Michael Karin, Dr Christophe Cataisson (NCI/NIH) and Dr Claire Sauvageot (Millennium Pharmaceuticals, Inc) for critique of the manuscript.
Funding Information:
1Tumor Biology Section, Head and Neck Surgery Branch, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD, USA; 2Howard Hughes Medical Institute-NIH Research Scholars Program, Bethesda, MD, USA; 3Clinical Research Training Program supported jointly by NIH and Pfizer Inc, Bethesda, MD, USA; 4Department of Radiation Oncology, Vanderbilt University Medical Center, Nashville, TN, USA and 5Millennium Pharmaceuticals, Inc., Cambridge, MA, USA. Correspondence: Dr Z Chen or Dr C Van Waes, Tumor Biology Section, Head and Neck Surgery Branch, NIDCD/National Institutes of Health, 10/5D55, MSC-1419, Bethesda, MD 20892-1419, USA. E-mail: [email protected] or [email protected] 6These authors contributed equally as the first author. 7Current address: Agios Pharmaceuticals, Cambridge, MA, USA. 8These authors contributed equally as senior authors. Received 25 September 2011; revised 7 January 2013; accepted 18 January 2013; published online 4 March 2013
PY - 2014/2/27
Y1 - 2014/2/27
N2 - The inhibitor-κB kinase-nuclear factor-κB (IKK-NF-κB) and epidermal growth factor receptor-activator protein-1 (EGFR-AP1) pathways are often co-activated and promote malignant behavior, but the underlying basis for this relationship is unclear. Resistance to inhibitors of IKKβ or EGFR is observed in head and neck squamous cell carcinomas (HNSCC). Here, we reveal that both IKKα and β contribute to nuclear activation of canonical and alternate NF-κB/REL family transcription factors, and overexpression of signal components that enhance co-activation of the EGFR-AP1 pathway. We observed that IKKα and IKKβ exhibit increased protein expression, nuclear localization, and phosphorylation in HNSCC tissues and cell lines. Individually, IKK activity varied among different cell lines, but overexpression of both IKKs induced the strongest NF-κB activation. Conversely, siRNA knock down of both IKKs significantly decreased nuclear localization and phosphorylation of canonical RELA and IκBα and alternative p52 and RELB subunits. Knock down of both IKKs more effectively inhibited NF-κB activation, broadly modulated gene expression and suppressed cell proliferation and migration. Global expression profiling revealed that NF-κB, cytokine, inflammatory response and growth factor signaling are among the top pathways and networks regulated by IKKs. Importantly, IKKα and IKKβ together promoted the expression and activity of transforming growth factor α, EGFR and AP1 transcription factors cJun, JunB and Fra1. Knock down of AP1 subunits individually decreased 8/15 (53%) of IKK-targeted genes sampled and similarly inhibited cell proliferation and migration. Mutations of NF-κB and AP1-binding sites abolished or decreased IKK-induced interleukin-8 (IL-8) promoter activity. Compounds such as wedelactone with dual IKK inhibitory activity and geldanomycins that block IKKα/β and EGFR pathways were more active than IKKβ-specific inhibitors in suppressing NF-κB activation and proliferation and inducing cell death. We conclude that IKKα and IKKβ cooperatively activate NF-κB and EGFR/AP1 networks of signaling pathways and contribute to the malignant phenotype and the intrinsic or acquired therapeutic resistance of HNSCC.
AB - The inhibitor-κB kinase-nuclear factor-κB (IKK-NF-κB) and epidermal growth factor receptor-activator protein-1 (EGFR-AP1) pathways are often co-activated and promote malignant behavior, but the underlying basis for this relationship is unclear. Resistance to inhibitors of IKKβ or EGFR is observed in head and neck squamous cell carcinomas (HNSCC). Here, we reveal that both IKKα and β contribute to nuclear activation of canonical and alternate NF-κB/REL family transcription factors, and overexpression of signal components that enhance co-activation of the EGFR-AP1 pathway. We observed that IKKα and IKKβ exhibit increased protein expression, nuclear localization, and phosphorylation in HNSCC tissues and cell lines. Individually, IKK activity varied among different cell lines, but overexpression of both IKKs induced the strongest NF-κB activation. Conversely, siRNA knock down of both IKKs significantly decreased nuclear localization and phosphorylation of canonical RELA and IκBα and alternative p52 and RELB subunits. Knock down of both IKKs more effectively inhibited NF-κB activation, broadly modulated gene expression and suppressed cell proliferation and migration. Global expression profiling revealed that NF-κB, cytokine, inflammatory response and growth factor signaling are among the top pathways and networks regulated by IKKs. Importantly, IKKα and IKKβ together promoted the expression and activity of transforming growth factor α, EGFR and AP1 transcription factors cJun, JunB and Fra1. Knock down of AP1 subunits individually decreased 8/15 (53%) of IKK-targeted genes sampled and similarly inhibited cell proliferation and migration. Mutations of NF-κB and AP1-binding sites abolished or decreased IKK-induced interleukin-8 (IL-8) promoter activity. Compounds such as wedelactone with dual IKK inhibitory activity and geldanomycins that block IKKα/β and EGFR pathways were more active than IKKβ-specific inhibitors in suppressing NF-κB activation and proliferation and inducing cell death. We conclude that IKKα and IKKβ cooperatively activate NF-κB and EGFR/AP1 networks of signaling pathways and contribute to the malignant phenotype and the intrinsic or acquired therapeutic resistance of HNSCC.
KW - AP1
KW - IKKα
KW - IKKβ
KW - NF-κB
KW - head and neck cancers
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U2 - 10.1038/onc.2013.49
DO - 10.1038/onc.2013.49
M3 - Article
C2 - 23455325
AN - SCOPUS:84896729984
SN - 0950-9232
VL - 33
SP - 1135
EP - 1147
JO - Oncogene
JF - Oncogene
IS - 9
ER -