Identification of a MET-eIF4G1 translational regulation axis that controls HIF-1α levels under hypoxia.
Details
Serval ID
serval:BIB_01640A4086EF
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Identification of a MET-eIF4G1 translational regulation axis that controls HIF-1α levels under hypoxia.
Journal
Oncogene
ISSN
1476-5594 (Electronic)
ISSN-L
0950-9232
Publication state
Published
Issued date
07/2018
Peer-reviewed
Oui
Volume
37
Number
30
Pages
4181-4196
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Publication Status: ppublish
Abstract
Poor oxygenation is a common hallmark of solid cancers that strongly associates with aggressive tumor progression and treatment resistance. While a hypoxia-inducible factor 1α (HIF-1α)-associated transcriptional overexpression of the hepatocyte growth factor (HGF) receptor tyrosine kinase (RTK) MET has been previously documented, any regulation of the HIF-1α system through MET downstream signaling in hypoxic tumors has not been yet described. By using MET-driven in vitro as well as ex vivo tumor organotypic fresh tissue models we report that MET targeting results in depletion of HIF-1α and its various downstream targets. Mechanistically, we provide evidence that MET regulates HIF-1α levels through a protein translation mechanism that relies on phosphorylation modulation of the eukaryotic initiation factor 4G1 (eIF4G1) on serine 1232 (Ser-1232). Targeted phosphoproteomics data demonstrate a significant drop in eIF4G1 Ser-1232 phosphorylation following MET targeting, which is linked to an increased affinity between eIF4G1 and eIF4E. Since phosphorylation of eIF4G1 on Ser-1232 is largely mediated through mitogen-activated protein kinase (MAPK), we show that expression of a constitutively active K-RAS variant is sufficient to abrogate the inhibitory effect of MET targeting on the HIF-1α pathway with subsequent resistance of tumor cells to MET targeting under hypoxic conditions. Analysis of The Cancer Genome Atlas data demonstrates frequent co-expression of MET, HIF-1α and eIF4G1 in various solid tumors and its impact on disease-free survival of non-small cell lung cancer patients. Clinical relevance of the MET-eIF4G1-HIF-1α pathway is further supported by a co-occurrence of their expression in common tumor regions of individual lung cancer patients.
Keywords
Animals, Carcinoma, Non-Small-Cell Lung/genetics, Cell Line, Tumor, Disease-Free Survival, Eukaryotic Initiation Factor-4G/genetics, Gene Expression Regulation, Neoplastic/genetics, Humans, Hypoxia/genetics, Hypoxia-Inducible Factor 1, alpha Subunit/genetics, Lung Neoplasms/genetics, Mice, Mitogen-Activated Protein Kinases/genetics, Phosphorylation/genetics, Proto-Oncogene Proteins c-met/genetics, Signal Transduction/genetics
Pubmed
Web of science
Create date
29/06/2020 9:33
Last modification date
30/06/2020 5:26