RESUMO
Pediatric hepatoblastoma (HB) is the most common primary liver malignancy in infants and children. With great diversity and plasticity, tumor-infiltrating neutrophils were one of the most determining factors for poor prognosis in many malignant tumors. In this study, through bulk RNA sequencing for sorted blood and tumor-infiltrated neutrophils and comparison of neutrophils in tumor and para-tumor tissue by single-cell sequencing, we found that intratumoral neutrophils were composed of heterogenous functional populations at different development stages. Our study showed that terminally differentiated neutrophils with active ferroptosis prevailed in tumor tissue, whereas, in para-tumor, pre-fate naïve neutrophils were dominant and ferroptotic neutrophils dispersed in a broad spectrum of cell maturation. Gene profiling and in vitro T-cell coculture experiment confirmed that one of main functional intratumoral neutrophils was mainly immunosuppressive, which relied on the activation of ferroptosis. Combining the bulk RNA-seq, scRNA-seq data, and immunochemistry staining of tumor samples, CXCL12/CXCR4 chemotaxis pathway was suggested to mediate the migration of neutrophils in tumors as CXCR4 highly expressed by intratumoral neutrophils and its ligand CXCL12 expressed much higher level in tumor than that in para-tumor. Moreover, our study pinpointed that infiltrated CXCR4hi neutrophils, regardless of their differential distribution of cell maturation status in HB tumor and para-tumor regions, were the genuine perpetrators for immune suppression. Our data characterized the ferroptosis-dependent immunosuppression energized by intratumoral CXCR4 expression neutrophils and suggest a potential cell target for cancer immunotherapies.
Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Lactente , Criança , Humanos , Neutrófilos , Hepatoblastoma/genética , Hepatoblastoma/metabolismo , Hepatoblastoma/patologia , Transdução de Sinais , Quimiotaxia , Neoplasias Hepáticas/patologia , Receptores CXCR4/metabolismoRESUMO
NK cells are one of key immune components in neuroblastoma (NB) surveillance and eradication. Glucose metabolism as a major source of fuel for NK activation is exquisitely regulated. Our data revealed a diminished NK activation and a disproportionally augmented CD56bright subset in NB. Further study showed that NK cells in NB presented with an arrested glycolysis accompanied by an elevated expression of the long noncoding RNA (lncRNA) EPB41L4A-AS1, a known crucial participant in glycolysis regulation, in the CD56bright NK subset. The inhibitory function of lncRNA EPB41L4A-AS1 was recapitulated. Interestingly, our study demonstrated that exosomal lncRNA EPB41L4A-AS1 was transferrable from CD56bright NK to CD56dim NK and was able to quench the glycolysis of target NK. Our data demonstrated that an arrested glycolysis in patient NK cells was associated with an elevated lncRNA in CD56bright NK subset and a cross-talk between heterogeneous NK subsets was achieved by transferring metabolic inhibitory lncRNA through exosomes.
Assuntos
Exossomos , Neuroblastoma , RNA Longo não Codificante , Humanos , Antígeno CD56 , Exossomos/metabolismo , Glicólise , Células Matadoras Naturais , Neuroblastoma/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismoRESUMO
T-cell exhaustion is one of the key reasons for attenuated T-cell cytotoxicity against tumours. At both the expression and epigenetic levels, a number of genes, including the transcription factor TOX, are believed to be implicated in regulating T-cell exhaustion. In the present study, we found that in NB patients, the ratio of exhausted T cells, featuring upregulated PD-1 and Tim-3, was increased. Meanwhile, the expression of inhibitory surface receptors, including Lag-3, CD160, VISTA and KLRG1, was also increased, but this was accompanied by a reduced ability to release the effector molecules IL-2, IFN-γ, TNF-α and Granzyme B in CD3+ T cells from NB patients. It is noteworthy that NB-derived memory T cells (Tm) showed more obvious exhausted characteristics than other T cells. Moreover, the T cells from NB patients possessed a higher potential for exhaustion conversion upon in vitro TCR stimulation in our time-course culture experiment. In NB patients, T-cell exhaustion was demonstrated to correlate with the elevated expression of TOX in freshly sorted CD3+ T cells as well as in anti-CD3 stimulated PBMCs. Most importantly, our data supported the idea that the hypomethylation of the TOX promoter may be one of the initiators that regulates TOX expression and enables TOX to play a crucial role in T-cell exhaustion reprogramming in NB patients.
Assuntos
Proteínas de Grupo de Alta Mobilidade/metabolismo , Neuroblastoma , Fatores de Transcrição , Linfócitos T CD8-Positivos/patologia , Regulação da Expressão Gênica , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , Fatores de Transcrição/genéticaRESUMO
Neuroblastoma (NB) is the most common extracranial solid tumor and the treatment efficacy of high-risk NB is unsatisfactory. γδT-cell-based adoptive cell transfer is a promising approach for high-risk NB treatment. Our previous study has revealed that γδT cells in NB patients exhibit a poor proliferation activity and a decreased anti-tumor capacity in vitro. In the present study, we found that IL-15 could effectively enhance the proliferation of NB γδT cells, to a level that remains lower than healthy controls though. In addition, IL-15-fostered NB γδT cells robustly boosted cell survival against apoptosis induced by cytokines depletion. Our data revealed that Mcl-1 was a key anti-apoptotic protein in IL-15-fostered γδT cells during cytokine withdrawal and its expression was regulated via the activation of STAT5 and ERK. In addition, IL-2 and IL-15-fostered γδT cells harbored higher levels of tumoricidal capacity which is also beneficial for γδ T-cell based immune therapy in NB. Understanding the survival control of γδT cells in a sub-optimal cytokine supportive microenvironment will expedite the clinical application of γδT cells for immunotherapy.
RESUMO
The mechanism of the characteristic intermittent hypoxia (IH) of obstructive sleep apnea syndrome (OSAS) on monocyte remain unclear. Our study found that OSAS children had a significantly upregulated expression in circulating proinflammatory cytokines IL-6 and IL-12, and endothelial injury markers VEGF and ICAM1. Association analysis revealed that the plasma TNFα, IL-1ß, IL-6, IL-10 and IL-12 concentration were negatively associated with the minimal SpO2, a negative index for disease severity. OSAS monocytes presented an inflammatory phenotype with higher mRNA levels of inflammatory cytokines. Importantly, we noted a significant decrease in T-cell immunoglobulin and mucin domain (Tim)-3 expression in OSAS monocytes with the increase of the plasma proinflammatory cytokines. In vitro assay demonstrated that IH induced THP-1 cell overactivation via NF-κB dependent pathway was inhibited by the Tim-3 signal. Our results indicated that activation of monocyte inflammatory responses is closely related to OSAS-induced IH, and negatively mediated by a Tim-3 signaling pathway.
Assuntos
Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Hipóxia/patologia , Monócitos/metabolismo , Apneia Obstrutiva do Sono/patologia , Receptor Celular 2 do Vírus da Hepatite A/genética , Humanos , Inflamação/imunologia , Molécula 1 de Adesão Intercelular/sangue , Subunidade p35 da Interleucina-12/sangue , Interleucina-6/sangue , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/sangueRESUMO
BACKGROUND: Henoch-Schonlein purpura (HSP) is the most common systemic vasculitis of the childhood. However, its mechanisms and pathogenesis still need more exploration. Natural killer (NK) cells are innate lymphocytes, and there is a growing appreciation that cellular metabolism is important in determining the immune responsiveness of lymphocytes. Thus, we aimed to analyze the NK cells phenotype and explore the association between glucose metabolism and NK cells function in HSP patients. RESULTS: A total number of 64 HSP patients and 34 healthy children were included. The HSP patients were divided into two groups according to whether accompanied with nephritis or not. NK cells in HSP patients without nephritis showed a reduced frequency in peripheral blood, a down-regulated expression of activating receptors both NKp30 and NKp46, and an attenuated cytotoxic function against tumor cells. In addition, the function impairment of NK cells was shown to exacerbate in HSPN. Our data further revealed an aberrant metabolic reprogramming of NK cells in HSP patients. Upon stimulation with cytokines (IL-15, IL-12 and IL-2), NK cells from healthy controls switched to an elevated glycolysis rate to support their effector function. By contrast, the glycolysis rate of activated NK cells in HSP group was not significantly up-regulated from the resting level possibly owing to the inhibition of mTORC1. CONCLUSIONS: Our study found that HSP patients were accompanied with dysfunction of NK cells. We concluded that the dysfunction of NK cells in HSP patients was induced with a decreased glycolysis rate and suggested that metabolic reprogramming of NK cells might be a player in the pathogenesis of HSP.
Assuntos
Glicólise/fisiologia , Vasculite por IgA/imunologia , Células Matadoras Naturais/imunologia , Células Cultivadas , Reprogramação Celular , Criança , Citocinas/metabolismo , Citotoxicidade Imunológica , Feminino , Humanos , Vasculite por IgA/metabolismo , Ativação Linfocitária , Masculino , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , Receptor 3 Desencadeador da Citotoxicidade Natural/metabolismo , NefriteRESUMO
Neuroblastoma (NB) is the most common solid extracranial malignancy in children with a considerable chance of metastatic progression. Prevalent evidence supports the anti-tumor role of γδT cells and these cells have been testing in clinical trials for constraining tumor growth. A small subpopulation of γδT cells releasing IL-17, however, were demonstrated to exert tumor-promoting effects in many aspects. In this study, we found an augment of IL-17+ γδT cells both in in vitro PAM-stimulated γδT-cell expanding culture and circulating γδT cells in NB patients. These patient-origin cells expanded in vitro by PAM in the presence of IL-17 polarizing condition were shown to promote the proliferation and migration of NB cells. Furthermore, an intrinsic preference for IL-17 polarization in NB γδT cells was revealed by mRNA microarray and Western Blot, which pointed to an up-regulated expression of multiple Th17-development related genes in addition to an increased phosphorylation level of STAT3.
Assuntos
Interleucina-17/imunologia , Linfócitos Intraepiteliais/imunologia , Neuroblastoma/imunologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Pré-Escolar , Feminino , Humanos , Masculino , Neuroblastoma/patologiaRESUMO
Chronic hepatitis B virus infection is a major risk factor for hepatocellular carcinoma. HBV infection affects lncRNA expression in infected cells, but the detailed mechanism and biological significance are not yet clear. In this study, we focused on exploring the function of the HBV-upregulated lncRNA SAMD12-AS1 in cell proliferation. We found that there is a higher level of SAMD12-AS1 expression in tumors than in adjacent nontumorous liver tissues. We showed that ectopic expression of SAMD12-AS1 promotes cell growth and blocks apoptosis, while knockdown of SAMD12-AS1 inhibits cell proliferation and enhances etoposide-induced apoptosis. Using RNA immunoprecipitation and mass spectrometry, we determined that SAMD12-AS1 interacts with NPM1 and confirmed that SAMD12-AS1(1-350) is required for the interaction with NPM1. As it is known that NPM1 interacts with the E3 ligase HDM2 and reduces HDM2-mediated p53 degradation, we examined whether SAMD12-AS1 can affect p53 stability. Overexpression of SAMD12-AS1 caused a reduction in p53 protein levels by shortening its half-life. Conversely, knockdown of SAMD12-AS1 prolonged the half-life of p53. We further demonstrated that SAMD12-AS1 increased the interaction of HDM2 and p53 and enhanced p53 ubiquitination. Our findings reveal that HBV-upregulated SAMD12-AS1 regulates cell proliferation and apoptosis via the NPM1-HDM2-p53 axis.
Assuntos
Apoptose/fisiologia , Proliferação de Células/fisiologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Proteínas Nucleares/metabolismo , RNA Longo não Codificante/fisiologia , Humanos , Proteínas do Tecido Nervoso/metabolismo , Nucleofosmina , Ligação Proteica , RNA Longo não Codificante/metabolismoRESUMO
Previously, we identified a set of long noncoding RNAs (lncRNAs) that were differentially expressed in influenza A virus (IAV)-infected cells. In this study, we focused on lnc-MxA, which is upregulated during IAV infection. We found that the overexpression of lnc-MxA facilitates the replication of IAV, while the knockdown of lnc-MxA inhibits viral replication. Further studies demonstrated that lnc-MxA is an interferon-stimulated gene. However, lnc-MxA inhibits the Sendai virus (SeV)- and IAV-induced activation of beta interferon (IFN-ß). A luciferase assay indicated that lnc-MxA inhibits the activation of the IFN-ß reporter upon stimulation with RIG-I, MAVS, TBK1, or active IRF3 (IRF3-5D). These data indicated that lnc-MxA negatively regulates the RIG-I-mediated antiviral immune response. A chromatin immunoprecipitation (ChIP) assay showed that the enrichment of IRF3 and p65 at the IFN-ß promoter in lnc-MxA-overexpressing cells was significantly lower than that in control cells, indicating that lnc-MxA interfered with the binding of IRF3 and p65 to the IFN-ß promoter. Chromatin isolation by RNA purification (ChIRP), triplex pulldown, and biolayer interferometry assays indicated that lnc-MxA can bind to the IFN-ß promoter. Furthermore, an electrophoretic mobility shift assay (EMSA) showed that lnc-MxA can form complexes with the IFN-ß promoter fragment. These results demonstrated that lnc-MxA can form a triplex with the IFN-ß promoter to interfere with the activation of IFN-ß transcription. Using a vesicular stomatitis virus (VSV) infection assay, we confirmed that lnc-MxA can repress the RIG-I-like receptor (RLR)-mediated antiviral immune response and influence the antiviral status of cells. In conclusion, we revealed that lnc-MxA is an interferon-stimulated gene (ISG) that negatively regulates the transcription of IFN-ß by forming an RNA-DNA triplex.IMPORTANCE IAV can be recognized as a nonself molecular pattern by host immune systems and can cause immune responses. However, the intense immune response induced by influenza virus, known as a "cytokine storm," can also cause widespread tissue damage (X. Z. J. Guo and P. G. Thomas, Semin Immunopathol 39:541-550, 2017, https://doi.org/10.1007/s00281-017-0636-y; S. Yokota, Nihon Rinsho 61:1953-1958, 2003; I. A. Clark, Immunol Cell Biol 85:271-273, 2007). Meanwhile, the detailed mechanisms involved in the balancing of immune responses in host cells are not well understood. Our studies reveal that, as an IFN-inducible gene, lnc-MxA functions as a negative regulator of the antiviral immune response. We uncovered the mechanism by which lnc-MxA inhibits the activation of IFN-ß transcription. Our findings demonstrate that, as an ISG, lnc-MxA plays an important role in the negative-feedback loop involved in maintaining immune homeostasis.