{"title":"Inhibition of PERK-mediated unfolded protein response acts as a switch for reversal of residual senescence and as senolytic therapy in glioblastoma.","authors":"Madhura Ketkar, Sanket Desai, Pranav Rana, Rahul Thorat, Sridhar Epari, Amit Dutt, Shilpee Dutt","doi":"10.1093/neuonc/noae134","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Glioblastoma due to recurrence is clinically challenging with 10-15 months overall survival. Previously we showed that therapy-induced senescence (TIS) in glioblastoma reverses causing recurrence. Here, we aim to delineate the TIS reversal mechanism for potential therapeutic intervention to prevent glioblastoma (GBM) recurrence.</p><p><strong>Methods: </strong>Residual senescent (RS) and end of residual senescence (ERS) cells were captured from GBM patient-derived primary-cultures and cell lines mimicking clinical scenarios. RNA-sequencing, transcript/protein validations, knock-down/inhibitor studies, ChIP RT-PCR, biochemical assays, and IHCs were performed for the mechanistics of TIS reversal. In vivo validations were conducted in GBM orthotopic mouse model.</p><p><strong>Results: </strong>Transcriptome analysis showed co-expression of endoplasmic reticulum (ER) stress-unfolded protein response (UPR) and senescence-associated secretory phenotype (SASP) with TIS induction and reversal. Robust SASP production and secretion by RS cells could induce senescence, Reactive oxygen specis (ROS), DNA damage, and ER stress in paracrine fashion independent of radiation. Neutralization of most significantly enriched cytokine from RS-secretome IL1β, suppressed SASP, and delayed senescence reversal. Mechanistically, with SASP and massive protein accumulation in ER, RS cells displayed stressed ER morphology, upregulated ER stress markers, and PERK pathway activation via peIF2α-ATF4-CHOP which was spontaneously resolved in ERS. ChIP RT-PCR showed CHOP occupancy at CXCL8/IL8, CDKN1A/p21, and BCL2L1/BCLXL aiding survival. PERK knockdown/inhibition with GSK2606414 in combination with radiation led to sustained ER stress and senescence without SASP. PERKi in RS functioned as senolytic via apoptosis and prevented recurrence in vitro and in vivo ameliorating overall survival.</p><p><strong>Conclusion: </strong>We demonstrate that PERK-mediated UPR regulates senescence reversal and its inhibition can be exploited as a potential seno-therapeutic option in glioblastoma.</p>","PeriodicalId":19377,"journal":{"name":"Neuro-oncology","volume":null,"pages":null},"PeriodicalIF":16.4000,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11534322/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Neuro-oncology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1093/neuonc/noae134","RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CLINICAL NEUROLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Glioblastoma due to recurrence is clinically challenging with 10-15 months overall survival. Previously we showed that therapy-induced senescence (TIS) in glioblastoma reverses causing recurrence. Here, we aim to delineate the TIS reversal mechanism for potential therapeutic intervention to prevent glioblastoma (GBM) recurrence.
Methods: Residual senescent (RS) and end of residual senescence (ERS) cells were captured from GBM patient-derived primary-cultures and cell lines mimicking clinical scenarios. RNA-sequencing, transcript/protein validations, knock-down/inhibitor studies, ChIP RT-PCR, biochemical assays, and IHCs were performed for the mechanistics of TIS reversal. In vivo validations were conducted in GBM orthotopic mouse model.
Results: Transcriptome analysis showed co-expression of endoplasmic reticulum (ER) stress-unfolded protein response (UPR) and senescence-associated secretory phenotype (SASP) with TIS induction and reversal. Robust SASP production and secretion by RS cells could induce senescence, Reactive oxygen specis (ROS), DNA damage, and ER stress in paracrine fashion independent of radiation. Neutralization of most significantly enriched cytokine from RS-secretome IL1β, suppressed SASP, and delayed senescence reversal. Mechanistically, with SASP and massive protein accumulation in ER, RS cells displayed stressed ER morphology, upregulated ER stress markers, and PERK pathway activation via peIF2α-ATF4-CHOP which was spontaneously resolved in ERS. ChIP RT-PCR showed CHOP occupancy at CXCL8/IL8, CDKN1A/p21, and BCL2L1/BCLXL aiding survival. PERK knockdown/inhibition with GSK2606414 in combination with radiation led to sustained ER stress and senescence without SASP. PERKi in RS functioned as senolytic via apoptosis and prevented recurrence in vitro and in vivo ameliorating overall survival.
Conclusion: We demonstrate that PERK-mediated UPR regulates senescence reversal and its inhibition can be exploited as a potential seno-therapeutic option in glioblastoma.
期刊介绍:
Neuro-Oncology, the official journal of the Society for Neuro-Oncology, has been published monthly since January 2010. Affiliated with the Japan Society for Neuro-Oncology and the European Association of Neuro-Oncology, it is a global leader in the field.
The journal is committed to swiftly disseminating high-quality information across all areas of neuro-oncology. It features peer-reviewed articles, reviews, symposia on various topics, abstracts from annual meetings, and updates from neuro-oncology societies worldwide.