PERK通過抑制STING信號增強抗腫瘤免疫
作者:
小柯機器人發布時間:2020/4/20 12:46:03
美國H. Lee Moffitt癌症中心和研究所Paulo C. Rodriguez研究小組發現,未摺疊蛋白反應中間蛋白PERK通過抑制STING信號調控癌症患者中髓樣細胞誘導的免疫抑制。相關論文於2020年4月14日發表在國際學術期刊《免疫》雜誌上。
研究人員探究了在腫瘤相關的髓樣來源抑制細胞(tumor-MDSCs)中,內源性激活PKR樣內質網(ER)激酶(PERK)在免疫抑制中的作用。PERK信號在腫瘤MDSC中增加,其缺失將MDSC轉變為髓樣細胞並激活CD8 + T細胞介導的抗癌免疫。
在PERK缺失的腫瘤MDSCs中, NRF2介導的抗氧化功能被破壞並且線粒體呼吸穩態受損。此外,在PERK缺失的MDSC中減少NRF2信號傳遞會引起胞質線粒體DNA升高,因此導致STING依賴的抗腫瘤I型幹擾素的表達。
重新激活NRF2信號、STING條件缺失或阻斷I型幹擾素受體I恢復了PERK缺失MDSC的免疫抑制潛能。這些發現證明了PERK在腫瘤MDSC中的關鍵作用,並揭示可以通過重編程生成腫瘤免疫抑制性骨髓以增強癌症免疫療法。
據了解,調控髓樣細胞浸潤到腫瘤的免疫極化機制亟待探究。這些信號的闡明將有助於利用更好的策略來恢復保護性抗腫瘤免疫。
附:英文原文
Title: The Unfolded Protein Response Mediator PERK Governs Myeloid Cell-Driven Immunosuppression in Tumors through Inhibition of STING Signaling
Author: Eslam Mohamed, Rosa A. Sierra, Jimena Trillo-Tinoco, Yu Cao, Patrick Innamarato, Kyle K. Payne, Alvaro de Mingo Pulido, Jessica Mandula, Shuzhong Zhang, Paul Thevenot, Subir Biswas, Sarah K. Abdalla, Tara Lee Costich, Kay Hnggi, Carmen M. Anadon, Elsa R. Flores, Eric B. Haura, Shikhar Mehrotra, Shari Pilon-Thomas, Brian Ruffell, David H. Munn, Juan R. Cubillos-Ruiz, Jose R. Conejo-Garcia, Paulo C. Rodriguez
Issue&Volume: 2020/04/14
Abstract: The primary mechanisms supporting immunoregulatory polarization of myeloid cells uponinfiltration into tumors remain largely unexplored. Elucidation of these signals couldenable better strategies to restore protective anti-tumor immunity. Here, we investigatedthe role of the intrinsic activation of the PKR-like endoplasmic reticulum (ER) kinase(PERK) in the immunoinhibitory actions of tumor-associated myeloid-derived suppressorcells (tumor-MDSCs). PERK signaling increased in tumor-MDSCs, and its deletion transformedMDSCs into myeloid cells that activated CD8+ T cell-mediated immunity against cancer. Tumor-MDSCs lacking PERK exhibited disruptedNRF2-driven antioxidant capacity and impaired mitochondrial respiratory homeostasis.Moreover, reduced NRF2 signaling in PERK-deficient MDSCs elicited cytosolic mitochondrialDNA elevation and, consequently, STING-dependent expression of anti-tumor type I interferon.Reactivation of NRF2 signaling, conditional deletion of STING, or blockade of typeI interferon receptor I restored the immunoinhibitory potential of PERK-ablated MDSCs.Our findings demonstrate the pivotal role of PERK in tumor-MDSC functionality andunveil strategies to reprogram immunosuppressive myelopoiesis in tumors to boost cancer immunotherapy.
DOI: 10.1016/j.immuni.2020.03.004
Source: https://www.cell.com/immunity/fulltext/S1074-7613(20)30117-5