Inhibition of mTOR-kinase destabilizes MYCN and is a potential therapy for MYCN-dependent tumors.
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Date
2016-09-06ICR Author
Author
Vaughan, L
Clarke, PA
Barker, K
Chanthery, Y
Gustafson, CW
Tucker, E
Renshaw, J
Raynaud, F
Li, X
Burke, R
Jamin, Y
Robinson, SP
Pearson, A
Maira, M
Weiss, WA
Workman, P
Chesler, L
Type
Journal Article
Metadata
Show full item recordAbstract
MYC oncoproteins deliver a potent oncogenic stimulus in several human cancers, making them major targets for drug development, but efforts to deliver clinically practical therapeutics have not yet been realized. In childhood cancer, aberrant expression of MYC and MYCN genes delineates a group of aggressive tumours responsible for a major proportion of pediatric cancer deaths. We designed a chemical-genetic screen that identifies compounds capable of enhancing proteasomal elimination of MYCN oncoprotein. We isolated several classes of compound that selectively kill MYCN expressing cells and we focus on inhibitors of PI3K/mTOR pathway in this study. We show that PI3K/mTOR inhibitors selectively killed MYCN-expressing neuroblastoma tumor cells, and induced significant apoptosis of transgenic MYCN-driven neuroblastoma tumors concomitant with elimination of MYCN protein in vivo. Mechanistically, the ability of these compounds to degrade MYCN requires complete blockade of mTOR but not PI3 kinase activity and we highlight NVP-BEZ235 as a PI3K/mTOR inhibitor with an ideal activity profile. These data establish that MYCN expression is a marker indicative of likely clinical sensitivity to mTOR inhibition, and provide a rationale for the selection of clinical candidate MYCN-destabilizers likely to be useful for the treatment of MYCN-driven cancers.
Collections
Subject
Cell Line, Tumor
Animals
Mice, Transgenic
Humans
Mice
Mice, Nude
Neuroblastoma
Imidazoles
Quinolines
Neoplasm Transplantation
Signal Transduction
Apoptosis
Gene Expression Regulation, Neoplastic
Phosphorylation
Transgenes
Phosphatidylinositol 3-Kinases
HEK293 Cells
TOR Serine-Threonine Kinases
Glycogen Synthase Kinase 3 beta
N-Myc Proto-Oncogene Protein
Mechanistic Target of Rapamycin Complex 1
Mechanistic Target of Rapamycin Complex 2
Research team
Clinical Pharmacology & Trials (including Drug Metabolism & Pharmacokinetics Group)
Signal Transduction & Molecular Pharmacology
Paediatric Solid Tumour Biology and Therapeutics
Pre-Clinical MRI
Hit Discovery & Structural Design
Language
eng
Date accepted
2016-06-01
License start date
2016-09
Citation
Oncotarget, 2016, 7 (36), pp. 57525 - 57544
Publisher
IMPACT JOURNALS LLC