RESUMO
Myeloid-derived suppressor cells (MDSCs) are pathologically activated neutrophils and monocytes with potent immunosuppressive activity that regulate immune responses in the tumor microenvironment. We identified a novel long noncoding RNA (lncRNA), named as lnc57Rik, in the MDSCs that controls their immunosuppressive functions. Lnc57Rik was induced in in vitro and in vivo inflammatory settings and upregulated the genes related to MDSC-mediated immunosuppression, including Arg-1, NOS2, NOX2, and COX2 Furthermore, Lnc57Rik can not only bind with the C/EBPß isoform liver-enriched activator protein to activate C/EBPß but also with the methyltransferase WD repeat-containing protein 5 that enables the enrichment of histone H3 trimethylated lysine 4 marks on the promoter regions of Arg-1, NOS2, NOX2, and COX2, eventually resulting in their transcriptional activation. Furthermore, the conserved human lnc57Rik has a similar function as murine lnc57Rik Taken together, upregulation of lnc57Rik in the tumor microenvironment promotes the immunosuppressive function of MDSCs.
Assuntos
Células Supressoras Mieloides , Neoplasias , RNA Longo não Codificante , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Histonas/metabolismo , Humanos , Lisina/metabolismo , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Microambiente Tumoral/genéticaRESUMO
OBJECTIVES: Cholesterol efflux has been thought to be the main and basic mechanism by which free cholesterol is transferred from extra hepatic cells to the liver or intestine for excretion. Salvianolic acid B (Sal B) has been widely used for the prevention and treatment of atherosclerotic diseases. Here, we sought to investigate the effects of Sal B on the cholesterol efflux in THP-1 macrophages. METHODS: After PMA-stimulated THP-1 cells were exposed to 50 mg/L of oxLDL and [(3)H] cholesterol (1.0 µCi/mL) for another 24 h, the effect of Sal B on cholesterol efflux was evaluated in the presence of apoA-1, HDL2 or HDL3. The expression of ATP binding cassette transporter A1 (ABCA1), peroxisome proliferator-activated receptor-gamma (PPAR-γ), and liver X receptor-alpha (LXRα) was detected both at protein and mRNA levels in THP-1 cells after the stimulation of Sal B. Meanwhile, specific inhibition of PPAR-γ and LXRα were performed to investigate the mechanism. RESULTS: The results showed that Sal B significantly accelerated apoA-I- and HDL-mediated cholesterol efflux in both dose- and time-dependent manners. Meanwhile, Sal B treatment also enhanced the expression of ABCA1 at both mRNA and protein levels. Then the data demonstrated that Sal B increased the expression of PPAR-γ and LXRα. And the application of specific agonists and inhibitors of further confirmed that Sal exert the function through PPAR-γ and LXRα. CONCLUSION: These results demonstrate that Sal B promotes cholesterol efflux in THP-1 macrophages through ABCA1/PPAR-γ/LXRα pathway.
Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Benzofuranos/farmacologia , Colesterol/metabolismo , Receptores Nucleares Órfãos/metabolismo , PPAR gama/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Apolipoproteína A-I/metabolismo , Transporte Biológico Ativo/efeitos dos fármacos , Linhagem Celular , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Lipoproteínas HDL2/metabolismo , Lipoproteínas HDL3/metabolismo , Receptores X do Fígado , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Receptores Nucleares Órfãos/antagonistas & inibidores , Receptores Nucleares Órfãos/genética , PPAR gama/antagonistas & inibidores , PPAR gama/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima/efeitos dos fármacosRESUMO
The activation of NLRC4 is a major host response against intracellular bacteria infection. However, NLRC4 activation after a host senses diverse stimuli is difficult to understand. Here, we found that the lncRNA LNCGM1082 plays a critical role in the activation of NLRC4. LNCGM1082 in macrophages affects the maturation of interleukin (IL)-1ß and pyroptotic cell death only after exposure to an NLRC4 ligand. Similar to NLRC4-/- mice, LNCGM1082-/- mice were highly sensitive to Salmonella Typhimurium (S. T) infection. LNCGM1082 deficiency in mouse or human macrophages inhibited IL-1ß maturation and pyroptosis. Mechanistically, LNCGM1082 induced the binding of PKCδ with NLRC4 in both mice and humans. In contrast, NLRC4 did not bind PKCδ in LNCGM1082-/- macrophages. The activity of the lncRNA LNCGM1082 induced by S. T may be mediated through TLR5 in the macrophages of both mice and humans. In summary, our data indicate that TLR5-mediated LNCGM1082 activity can promote the binding of PKCδ with NLRC4 to activate NLRC4 and induce resistance to bacterial infection.
Assuntos
RNA Longo não Codificante , Infecções por Salmonella , Animais , Humanos , Camundongos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/metabolismo , Inflamassomos/metabolismo , Camundongos Endogâmicos C57BL , Receptor 5 Toll-Like/metabolismoRESUMO
Macrophages, which can secret various inflammation mediators, have an essential role in tumor growth and metastasis. However, the mechanism(s) to regulate the production of inflammation mediator is not completely clear. Here we found that TRIM 59 could inhibit the production of NO and the expression of inducible nitric oxide synthase (iNOS), cytochrome c oxidase subunit2 (COX2) and TNFα. TRIM59 mediated suppression on nitric oxide (NO) production is through inhibiting the activation of JAK2-STAT1 signal pathway. In response to LPS, TRIM59 in macrophages was translocated from cytoplasm to nucleus and directly bound with STAT1. During this process, TRIM59 could recruit much more PIAS1 to bind with STAT1 to suppress the activation of STAT1. Finally, TRIM59 modified macrophages could promote tumor growth. Thus, TRIM59 mediated suppression on NO production by promoting the binding of PIAS1 and STAT1 in macrophages may regulate tumor growth.
Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/metabolismo , Óxido Nítrico/metabolismo , Proteínas Inibidoras de STAT Ativados/metabolismo , Fator de Transcrição STAT1/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Janus Quinase 2/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/transplante , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação , Ligação Proteica , Proteínas Inibidoras de STAT Ativados/genética , Células RAW 264.7 , Proteínas com Motivo Tripartido/genética , Carga Tumoral , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/transplanteRESUMO
Macrophages are mainly divided into two populations, which play a different role in physiological and pathological conditions. The differentiation of these cells may be regulated by transcription factors. However, it is unclear how to modulate these transcription factors to affect differentiation of these cells. Here, we found that lncLy6C, a novel ultraconserved lncRNA, promotes differentiation of Ly6Chigh inflammatory monocytes into Ly6Clow/neg resident macrophages. We demonstrate that gut microbiota metabolites butyrate upregulates the expression of lncLy6C. LncLy6C deficient mice had markedly increased Ly6Chigh pro-inflammatory monocytes and reduced Ly6Cneg resident macrophages. LncLy6C not only bound with transcription factor C/EBPß but also bound with multiple lysine methyltransferases of H3K4me3 to specifically promote the enrichment of C/EBPß and H3K4me3 marks on the promoter region of Nr4A1, which can promote Ly6Chigh into Ly6Cneg macrophages. As a result, lncLy6C causes the upregulation of Nr4A1 to promote Ly6Chigh inflammatory monocytes to differentiate into Ly6Cint/neg resident macrophages.
RESUMO
BACKGROUND: Programmed cell death protein 1 (PD-1), as an immune checkpoint cell membrane receptor, negatively regulates T cell activation via its immune receptor, the tyrosine-based switch motif (ITSM). The purpose of this research was to evaluate the antitumor activity T cells with the ITSM mutation of PD-1 on non-small cell lung cancer (NSCLC) in vitro and in vivo. METHODS: In this study, the tyrosine of ITSM in cytotoxic T cells was mutated using the adenine base editor (ABE)-xCas9 system to evaluate its effect on the antitumor activity of T cells against NSCLC. RESULTS: Results showed that the PD-1-deficient T cells enhanced the death of the cocultured NSCLC cells compared with the normal T cells and saline solution. PD-1-deficient T cells also changed the interleukin 2(IL-2), interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), and granulocyte-macrophage colony-stimulating factor (GM-CSF) secretion of T cells compared with those of the normal T cells. The effectiveness of ITSM mutation in enhancing the antitumor activity of PD-1-deficient T cells was verified in vivo by using a mouse xenograft model. The xenografted mice treated with PD-1-deficient T cells demonstrated repressed tumor growth of the NSCLC cells compared with those treated with normal T cells and saline solution. CONCLUSIONS: The mutation of ITSM in cytotoxic T cell via the ABE-xCas9 system can significantly enhance the antitumor activity of T cells.