Gonzalo Almanza, Stephen Searles, Maurizio Zanetti
{"title":"Delivery of miR-214 via extracellular vesicles downregulates <i>Xbp1</i> expression and pro-inflammatory cytokine genes in macrophages.","authors":"Gonzalo Almanza, Stephen Searles, Maurizio Zanetti","doi":"10.20517/evcna.2023.64","DOIUrl":null,"url":null,"abstract":"<p><strong>Aim: </strong>Tumor-infiltrating macrophages are tumor-promoting and show activation of the unfolded protein response (UPR). The transcription factor X-box binding protein 1 (XBP1) is a conserved element of the UPR. Upon activation, the UPR mediates the transcriptional activation of pro-inflammatory cytokines and immune suppressive factors, hence contributing to immune dysregulation in the tumor microenvironment (TME). miR-214 is a short non-coding miRNA that targets the 3'-UTR of the Xbp1 transcript. Here, we tested a new method to efficiently deliver miR-214 to macrophages as a potential new therapeutic approach.</p><p><strong>Methods: </strong>We generated miR-214-laden extracellular vesicles (iEV-214) in a murine B cell and demonstrated that iEV-214 were enriched in miR-214 between 1,500 - 2,000 fold relative to control iEVs.</p><p><strong>Results: </strong>Bone marrow-derived macrophages (BMDM) treated with iEV-214 for 24 h underwent a specific enrichment in miR-214, suggesting transfer of the miR-214 payload from the iEVs to macrophages. iEV-214 treatment of BMDM markedly reduced (> 50%) Xbp1 transcription under endoplasmic reticulum stress conditions compared to controls. Immune-related genes downstream of XBP1s (<i>Il-6</i>, <i>Il-23p19</i>, and <i>Arg1</i>) were also reduced by 69%, 51%, and 34%, respectively.</p><p><strong>Conclusions: </strong>Together, these data permit to conclude that iEV-214 are an efficient strategy to downregulate the expression of <i>Xbp1</i> mRNA and downstream genes in macrophages. We propose miRNA-laden iEVs are a new approach to target macrophages and control immune dysregulation in the TME.</p>","PeriodicalId":73008,"journal":{"name":"Extracellular vesicles and circulating nucleic acids","volume":"5 2","pages":"249-258"},"PeriodicalIF":0.0000,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11308798/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Extracellular vesicles and circulating nucleic acids","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.20517/evcna.2023.64","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/5/28 0:00:00","PubModel":"Epub","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Aim: Tumor-infiltrating macrophages are tumor-promoting and show activation of the unfolded protein response (UPR). The transcription factor X-box binding protein 1 (XBP1) is a conserved element of the UPR. Upon activation, the UPR mediates the transcriptional activation of pro-inflammatory cytokines and immune suppressive factors, hence contributing to immune dysregulation in the tumor microenvironment (TME). miR-214 is a short non-coding miRNA that targets the 3'-UTR of the Xbp1 transcript. Here, we tested a new method to efficiently deliver miR-214 to macrophages as a potential new therapeutic approach.
Methods: We generated miR-214-laden extracellular vesicles (iEV-214) in a murine B cell and demonstrated that iEV-214 were enriched in miR-214 between 1,500 - 2,000 fold relative to control iEVs.
Results: Bone marrow-derived macrophages (BMDM) treated with iEV-214 for 24 h underwent a specific enrichment in miR-214, suggesting transfer of the miR-214 payload from the iEVs to macrophages. iEV-214 treatment of BMDM markedly reduced (> 50%) Xbp1 transcription under endoplasmic reticulum stress conditions compared to controls. Immune-related genes downstream of XBP1s (Il-6, Il-23p19, and Arg1) were also reduced by 69%, 51%, and 34%, respectively.
Conclusions: Together, these data permit to conclude that iEV-214 are an efficient strategy to downregulate the expression of Xbp1 mRNA and downstream genes in macrophages. We propose miRNA-laden iEVs are a new approach to target macrophages and control immune dysregulation in the TME.