Cargando…

Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma

BACKGROUND: Cutaneous melanoma is the most serious skin malignancy and new therapeutic strategies are needed for advanced melanoma. TP53 mutations are rare in cutaneous melanoma and hence activation of wild-type p53 is a potential therapeutic strategy in cutaneous melanoma. Here, we investigated the...

Descripción completa

Detalles Bibliográficos
Autores principales: Wu, Chiao-En, Esfandiari, Arman, Ho, Yi-Hsuan, Wang, Nan, Mahdi, Ahmed Khairallah, Aptullahoglu, Erhan, Lovat, Penny, Lunec, John
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5830592/
https://www.ncbi.nlm.nih.gov/pubmed/29235570
http://dx.doi.org/10.1038/bjc.2017.433
_version_ 1783303023866413056
author Wu, Chiao-En
Esfandiari, Arman
Ho, Yi-Hsuan
Wang, Nan
Mahdi, Ahmed Khairallah
Aptullahoglu, Erhan
Lovat, Penny
Lunec, John
author_facet Wu, Chiao-En
Esfandiari, Arman
Ho, Yi-Hsuan
Wang, Nan
Mahdi, Ahmed Khairallah
Aptullahoglu, Erhan
Lovat, Penny
Lunec, John
author_sort Wu, Chiao-En
collection PubMed
description BACKGROUND: Cutaneous melanoma is the most serious skin malignancy and new therapeutic strategies are needed for advanced melanoma. TP53 mutations are rare in cutaneous melanoma and hence activation of wild-type p53 is a potential therapeutic strategy in cutaneous melanoma. Here, we investigated the WIP1 inhibitor, GSK2830371, and MDM2–p53 binding antagonists (nutlin-3, RG7388 and HDM201) alone and in combination treatment in cutaneous melanoma cell lines and explored the mechanistic basis of these responses in relation to the genotype and induced gene expression profile of the cells. METHODS: A panel of three p53(WT) (A375, WM35 and C8161) and three p53(MUT) (WM164, WM35-R and CHL-1) melanoma cell lines were used. The effects of MDM2 and WIP1 inhibition were evaluated by growth inhibition and clonogenic assays, immunoblotting, qRT–PCR gene expression profiling and flow cytometry. RESULTS: GSK2830371, at doses (⩽10 μM) that alone had no growth-inhibitory or cytotoxic effects on the cells, nevertheless significantly potentiated the growth-inhibitory and clonogenic cell killing effects of MDM2 inhibitors in p53(WT) but not p53(MUT) melanoma cells, indicating the potentiation worked in a p53-dependent manner. The siRNA-mediated knockdown of p53 provided further evidence to support the p53 dependence. GSK2830371 increased p53 stabilisation through Ser15 phosphorylation and consequent Lys382 acetylation, and decreased ubiquitination and proteasome-dependent degradation when it was combined with MDM2 inhibitors. These changes were at least partly ATM mediated, shown by reversal with the ATM inhibitor (KU55933). GSK2830371 enhanced the induction of p53 transcriptional target genes, cell cycle arrest and apoptosis. CONCLUSIONS: GSK2830371, a WIP1 inhibitor, at doses with no growth-inhibitory activity alone, potentiated the growth-inhibitory and cytotoxic activity of MDM2 inhibitors by increasing phosphorylation, acetylation and stabilisation of p53 in cutaneous melanoma cells in a functional p53-dependent manner.
format Online
Article
Text
id pubmed-5830592
institution National Center for Biotechnology Information
language English
publishDate 2018
publisher Nature Publishing Group
record_format MEDLINE/PubMed
spelling pubmed-58305922019-02-20 Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma Wu, Chiao-En Esfandiari, Arman Ho, Yi-Hsuan Wang, Nan Mahdi, Ahmed Khairallah Aptullahoglu, Erhan Lovat, Penny Lunec, John Br J Cancer Translational Therapeutics BACKGROUND: Cutaneous melanoma is the most serious skin malignancy and new therapeutic strategies are needed for advanced melanoma. TP53 mutations are rare in cutaneous melanoma and hence activation of wild-type p53 is a potential therapeutic strategy in cutaneous melanoma. Here, we investigated the WIP1 inhibitor, GSK2830371, and MDM2–p53 binding antagonists (nutlin-3, RG7388 and HDM201) alone and in combination treatment in cutaneous melanoma cell lines and explored the mechanistic basis of these responses in relation to the genotype and induced gene expression profile of the cells. METHODS: A panel of three p53(WT) (A375, WM35 and C8161) and three p53(MUT) (WM164, WM35-R and CHL-1) melanoma cell lines were used. The effects of MDM2 and WIP1 inhibition were evaluated by growth inhibition and clonogenic assays, immunoblotting, qRT–PCR gene expression profiling and flow cytometry. RESULTS: GSK2830371, at doses (⩽10 μM) that alone had no growth-inhibitory or cytotoxic effects on the cells, nevertheless significantly potentiated the growth-inhibitory and clonogenic cell killing effects of MDM2 inhibitors in p53(WT) but not p53(MUT) melanoma cells, indicating the potentiation worked in a p53-dependent manner. The siRNA-mediated knockdown of p53 provided further evidence to support the p53 dependence. GSK2830371 increased p53 stabilisation through Ser15 phosphorylation and consequent Lys382 acetylation, and decreased ubiquitination and proteasome-dependent degradation when it was combined with MDM2 inhibitors. These changes were at least partly ATM mediated, shown by reversal with the ATM inhibitor (KU55933). GSK2830371 enhanced the induction of p53 transcriptional target genes, cell cycle arrest and apoptosis. CONCLUSIONS: GSK2830371, a WIP1 inhibitor, at doses with no growth-inhibitory activity alone, potentiated the growth-inhibitory and cytotoxic activity of MDM2 inhibitors by increasing phosphorylation, acetylation and stabilisation of p53 in cutaneous melanoma cells in a functional p53-dependent manner. Nature Publishing Group 2018-02-20 2017-12-12 /pmc/articles/PMC5830592/ /pubmed/29235570 http://dx.doi.org/10.1038/bjc.2017.433 Text en Copyright © 2018 Cancer Research UK http://creativecommons.org/licenses/by-nc-sa/4.0/ From twelve months after its original publication, this work is licensed under the Creative Commons Attribution-NonCommercial-Share Alike 4.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/4.0/
spellingShingle Translational Therapeutics
Wu, Chiao-En
Esfandiari, Arman
Ho, Yi-Hsuan
Wang, Nan
Mahdi, Ahmed Khairallah
Aptullahoglu, Erhan
Lovat, Penny
Lunec, John
Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma
title Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma
title_full Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma
title_fullStr Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma
title_full_unstemmed Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma
title_short Targeting negative regulation of p53 by MDM2 and WIP1 as a therapeutic strategy in cutaneous melanoma
title_sort targeting negative regulation of p53 by mdm2 and wip1 as a therapeutic strategy in cutaneous melanoma
topic Translational Therapeutics
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5830592/
https://www.ncbi.nlm.nih.gov/pubmed/29235570
http://dx.doi.org/10.1038/bjc.2017.433
work_keys_str_mv AT wuchiaoen targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma
AT esfandiariarman targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma
AT hoyihsuan targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma
AT wangnan targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma
AT mahdiahmedkhairallah targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma
AT aptullahogluerhan targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma
AT lovatpenny targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma
AT lunecjohn targetingnegativeregulationofp53bymdm2andwip1asatherapeuticstrategyincutaneousmelanoma