c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.

Choroidal melanoma is the most common primary malignant intraocular tumor, and very few effective therapies are available to treat it. Our study aimed to understand whether pemetrexed plus cisplatin exerts a beneficial synergistic effect in human choroidal melanoma cells and to delineate the underly...

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Main Authors: Xiaofei Zhao, Feng Kong, Lei Wang, Han Zhang
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC5581197?pdf=render
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author Xiaofei Zhao
Feng Kong
Lei Wang
Han Zhang
author_facet Xiaofei Zhao
Feng Kong
Lei Wang
Han Zhang
author_sort Xiaofei Zhao
collection DOAJ
description Choroidal melanoma is the most common primary malignant intraocular tumor, and very few effective therapies are available to treat it. Our study aimed to understand whether pemetrexed plus cisplatin exerts a beneficial synergistic effect in human choroidal melanoma cells and to delineate the underlying molecular mechanism. To accomplish these aims, we treated choroidal melanoma cells with pemetrexed and cisplatin and assessed cell survival with SRB and MTT assays. Proteins were detected using western blotting analysis. NOXA and CHOP were knocked down with siRNA. We found that pemetrexed or cisplatin alone inhibited survival and induced apoptosis in human choroidal melanoma cells. Furthermore, the expression levels of c-FLIP, an anti-apoptotic protein in the extrinsic apoptosis pathway, and Mcl-1, an anti-apoptotic protein in the intrinsic apoptosis pathway, were decreased by pemetrexed or cisplatin respectively, while the expression of a pro-apoptotic protein in the intrinsic apoptosis pathway, NOXA, was up-regulated. Moreover, pemetrexed or cisplatin alone increased the protein expression of the endoplasmic reticulum stress markers IRE1α, Bip and CHOP. Silencing CHOP expression reduced NOXA expression. These findings suggest that the pemetrexed or cisplatin induced intrinsic apoptosis via activation of the ER stress response. Importantly, combining the two compounds more strongly induced apoptosis. Following the cotreatment, CHOP and NOXA expression increased, while c-FLIP and Mcl-1 expression decreased, and these effects were more pronounced than when using either compound alone. This result suggests that pemetrexed and cisplatin synergistically activate ER stress response-induced apoptosis in choroidal melanoma cells. To summarize, the c-FLIP and NOXA/Mcl-1 axis participated in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells. Intrinsic apoptosis was induced via activation of the ER stress response. Our study provides important mechanistic insights into potential cancer treatment with pemetrexed plus cisplatin and enriches our understanding of human choroidal melanoma.
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spelling doaj.art-c8fdb6b883cc429892ec4e3e1086a0482022-12-21T21:58:14ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01129e018413510.1371/journal.pone.0184135c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.Xiaofei ZhaoFeng KongLei WangHan ZhangChoroidal melanoma is the most common primary malignant intraocular tumor, and very few effective therapies are available to treat it. Our study aimed to understand whether pemetrexed plus cisplatin exerts a beneficial synergistic effect in human choroidal melanoma cells and to delineate the underlying molecular mechanism. To accomplish these aims, we treated choroidal melanoma cells with pemetrexed and cisplatin and assessed cell survival with SRB and MTT assays. Proteins were detected using western blotting analysis. NOXA and CHOP were knocked down with siRNA. We found that pemetrexed or cisplatin alone inhibited survival and induced apoptosis in human choroidal melanoma cells. Furthermore, the expression levels of c-FLIP, an anti-apoptotic protein in the extrinsic apoptosis pathway, and Mcl-1, an anti-apoptotic protein in the intrinsic apoptosis pathway, were decreased by pemetrexed or cisplatin respectively, while the expression of a pro-apoptotic protein in the intrinsic apoptosis pathway, NOXA, was up-regulated. Moreover, pemetrexed or cisplatin alone increased the protein expression of the endoplasmic reticulum stress markers IRE1α, Bip and CHOP. Silencing CHOP expression reduced NOXA expression. These findings suggest that the pemetrexed or cisplatin induced intrinsic apoptosis via activation of the ER stress response. Importantly, combining the two compounds more strongly induced apoptosis. Following the cotreatment, CHOP and NOXA expression increased, while c-FLIP and Mcl-1 expression decreased, and these effects were more pronounced than when using either compound alone. This result suggests that pemetrexed and cisplatin synergistically activate ER stress response-induced apoptosis in choroidal melanoma cells. To summarize, the c-FLIP and NOXA/Mcl-1 axis participated in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells. Intrinsic apoptosis was induced via activation of the ER stress response. Our study provides important mechanistic insights into potential cancer treatment with pemetrexed plus cisplatin and enriches our understanding of human choroidal melanoma.http://europepmc.org/articles/PMC5581197?pdf=render
spellingShingle Xiaofei Zhao
Feng Kong
Lei Wang
Han Zhang
c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.
PLoS ONE
title c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.
title_full c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.
title_fullStr c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.
title_full_unstemmed c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.
title_short c-FLIP and the NOXA/Mcl-1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells.
title_sort c flip and the noxa mcl 1 axis participate in the synergistic effect of pemetrexed plus cisplatin in human choroidal melanoma cells
url http://europepmc.org/articles/PMC5581197?pdf=render
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