SIRT1 promotes N-Myc oncogenesis through a positive feedback loop involving the effects of MKP3 and ERK on N-Myc protein stability.

The N-Myc oncoprotein is a critical factor in neuroblastoma tumorigenesis which requires additional mechanisms converting a low-level to a high-level N-Myc expression. N-Myc protein is stabilized when phosphorylated at Serine 62 by phosphorylated ERK protein. Here we describe a novel positive feedba...

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Bibliographic Details
Main Authors: Glenn M Marshall, Pei Y Liu, Samuele Gherardi, Christopher J Scarlett, Antonio Bedalov, Ning Xu, Nuncio Iraci, Emanuele Valli, Dora Ling, Wayne Thomas, Margo van Bekkum, Eric Sekyere, Kacper Jankowski, Toby Trahair, Karen L Mackenzie, Michelle Haber, Murray D Norris, Andrew V Biankin, Giovanni Perini, Tao Liu
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2011-06-01
Series:PLoS Genetics
Online Access:http://europepmc.org/articles/PMC3116909?pdf=render
Description
Summary:The N-Myc oncoprotein is a critical factor in neuroblastoma tumorigenesis which requires additional mechanisms converting a low-level to a high-level N-Myc expression. N-Myc protein is stabilized when phosphorylated at Serine 62 by phosphorylated ERK protein. Here we describe a novel positive feedback loop whereby N-Myc directly induced the transcription of the class III histone deacetylase SIRT1, which in turn increased N-Myc protein stability. SIRT1 binds to Myc Box I domain of N-Myc protein to form a novel transcriptional repressor complex at gene promoter of mitogen-activated protein kinase phosphatase 3 (MKP3), leading to transcriptional repression of MKP3, ERK protein phosphorylation, N-Myc protein phosphorylation at Serine 62, and N-Myc protein stabilization. Importantly, SIRT1 was up-regulated, MKP3 down-regulated, in pre-cancerous cells, and preventative treatment with the SIRT1 inhibitor Cambinol reduced tumorigenesis in TH-MYCN transgenic mice. Our data demonstrate the important roles of SIRT1 in N-Myc oncogenesis and SIRT1 inhibitors in the prevention and therapy of N-Myc-induced neuroblastoma.
ISSN:1553-7390
1553-7404