PEITC-mediated inhibition of mRNA translation is associated with both inhibition of mTORC1 and increased eIF2alpha phosphorylation in established cell lines and primary human leukemia cells


Yeomans, Alison, Lemm, Elizabeth, Wilmore, Sarah, Cavell, Breeze, Valle-Argos, Beatriz, Krysov, Sergey, Hidalgo, Marina, Leonard, Elodie, Willis, Anne E., Forconi, Francesco, Stevenson, Freda, Steele, Andrew, Coldwell, Mark and Packham, Graham (2016) PEITC-mediated inhibition of mRNA translation is associated with both inhibition of mTORC1 and increased eIF2alpha phosphorylation in established cell lines and primary human leukemia cells Oncotarget, pp. 1-13. (doi:10.18632/oncotarget.11655). (PMID:27579538).

Download

[img] PDF __soton.ac.uk_ude_PersonalFiles_Users_spm2_mydocuments_11655-175919-1-PB.pdf - Version of Record
Available under License Other.

Download (9MB)
[img] PDF __soton.ac.uk_ude_PersonalFiles_Users_spm2_mydocuments_Supplementary Materials11655-175927-1-SP.pdf - Other
Available under License Other.

Download (1MB)

Description/Abstract

Increased mRNA translation drives carcinogenesis and is an attractive target for the development of new anti-cancer drugs. In this work, we investigated effects of phenethylisothiocyanate (PEITC), a phytochemical with chemopreventive and anti-cancer activity, on mRNA translation. PEITC rapidly inhibited global mRNA translation in human breast cancer-derived MCF7 cells and mouse embryonic fibroblasts (MEFs). In addition to the known inhibitory effects of PEITC on mTORC1 activity, we demonstrate that PEITC increased eIF2? phosphorylation. PEITC also increased formation of stress granules which are typically associated with eIF2? phosphorylation and accumulation of translationally stalled mRNAs. Analysis of genetically modified MEFs demonstrated that optimal inhibition of global mRNA translation by PEITC was dependent on eIF2? phosphorylation, but not mTORC1 inhibition. We extended this study into primary leukemic B cells derived from patients with chronic lymphocytic leukaemia (CLL). CLL cells were stimulated in vitro with anti-IgM to mimic binding of antigen, a major driver of this leukemia. In CLL cells, PEITC increased eIF2? phosphorylation, inhibited anti-IgM-induced mTORC1 activation and decreased both basal and anti-IgM-induced global mRNA translation. PEITC also inhibited transcription and translation of MYC mRNA and accumulation of the MYC oncoprotein, in anti-IgM-stimulated cells. Moreover, treatment of CLL cells with PEITC and the BTK kinase inhibitor ibrutinib decreased anti-IgM-induced translation and induced cell death to a greater extent than either agent alone. Therefore, PEITC can inhibit both global and mRNA specific translation (including MYC) via effects on multiple regulatory pathways. Inhibition of mRNA translation may contribute to the chemopreventive and anti-cancer effects of PEITC.

Item Type: Article
Digital Object Identifier (DOI): doi:10.18632/oncotarget.11655
ISSNs: 1949-2553 (print)
Organisations: Cancer Sciences
ePrint ID: 400331
Date :
Date Event
27 July 2016Accepted/In Press
27 August 2016Published
Date Deposited: 14 Sep 2016 14:26
Last Modified: 22 Feb 2017 03:36
Further Information:Google Scholar
URI: http://eprints.soton.ac.uk/id/eprint/400331

Actions (login required)

View Item View Item