miR-106b-25/miR-17-92 clusters: Polycistrons with oncogenic roles in hepatocellular carcinoma

MicroRNAs are small endogenously expressed RNA molecules which are involved in the process of silencing gene expression through translational regulation. The polycistronic miR-17-92 cluster is the first microRNA cluster shown to play a role in tumorigenesis. It has two other paralogs in the human genome, the miR-106b-25 cluster and the miR-106a-363 cluster. Collectively, the microRNAs encoded by these clusters can be further grouped based on the seed sequences into four families, namely the miR-17, the miR-92, the miR-18 and the miR-19 families. Over-expression of the miR-106b-25 and miR-17-92 clusters has been reported not only during the development of cirrhosis but also subsequently during the development of hepatocellular carcinoma. Members of these clusters have also been shown to affect the replication of hepatitis B and hepatitis C viruses. Various targets of these microRNAs have been identified, and these targets are involved in tumor growth, cell survival and metastasis. In this review, we first describe the regulation of these clusters by c-Myc and E2F1, and how the members of these clusters in turn regulate E2F1 expression forming an auto-regulatory loop. In addition, the roles of the various members of the clusters in affecting relevant target gene expression in the pathogenesis of hepatocellular carcinoma will also be discussed.     

Temporal expression of microRNA cluster miR-17-92 regulates effector and memory CD8+ T-cell differentiation

MicroRNAs are important regulators of various developmental and physiological processes. However, their roles in the CD8(+) T-cell response are not well understood. Using an acute viral infection model, we show that microRNAs of the miR-17-92 cluster are strongly induced after T-cell activation, down-regulated after clonal expansion, and further silenced during memory development. miR-17-92 promotes cell-cycle progression of effector CD8(+) T cells, and its expression is critical to the rapid expansion of these cells. However, excessive miR-17-92 expression enhances mammalian target of rapamycin (mTOR) signaling and strongly skews the differentiation toward short-lived terminal effector cells. Failure to down-regulate miR-17-92 leads to a gradual loss of memory cells and defective central memory cell development. Therefore, our results reveal a temporal expression pattern of miR-17-92 by antigen-specific CD8(+) T cells during viral infection, the precise control of which is critical to the effector expansion and memory differentiation of CD8(+) T cells.     

MicroRNA Expression Profile Reveals miR-17-92 and miR-143-145 Cluster in Synchronous Colorectal Cancer

The expression of abnormal microRNA (miRNA, miR) is a ubiquitous feature of colorectal cancer (CRC). The pathological features and clinical behaviors of synchronous CRC have been comprehensively described; however, the expression profile of miRNA and small nucleolar RNA (snoRNA) in synchronous CRC has not been elucidated. In the present study, the expression profile of miRNA and snoRNA in 5 synchronous CRCs, along with the matched normal colorectal tissue was evaluated by microarray. Function and pathway analyses of putative targets, predicted from miRNA–mRNA interaction, were performed. Moreover, we analyzed clinicopathological and molecular characteristics of 22 patients with synchronous CRC and 579 solitary CRCs in a retrospective cohort study. We found a global dysregulation of miRNAs, including an oncogenic miR-17-92 cluster and oncosuppressive miR-143-145 cluster, and snoRNAs in synchronous CRC. Differential miRNA rather than snoRNA expression was robust enough to distinguish synchronous cancer from normal mucosa. Function analysis of putative targets suggested that miRNA clusters may modulate multiple effectors of oncogenic pathways involved in the pathogenesis of synchronous CRC. A comparison of normal mucosa between synchronous and solitary CRC suggested a differential genetic background of synchronous CRC from solitary CRC during carcinogenesis. Compared with solitary cancer patients, synchronous cases exhibited multiple extra-colonic cancers (P = 0.012), coexistence of adenoma (P = 0.012), microsatellite instability (P = 0.024), and less glucose transporter 1 (P = 0.037). Aberrant miRNA expression profiles could potentially be used as a diagnostic tool for synchronous CRC. Our findings represent the first comprehensive miRNA and snoRNA expression signatures for synchronous CRC, implicating that the miRNAs and snoRNAs may present therapeutic targets for synchronous CRC.     

血清miR-92a-1-5p及miR-92a-2-5p表达水平与老年卒中后抑郁的关系

目的 分析血清微小核糖核酸-92a-1-5p ( miR-92a-1-5p)、 miR-92a-2-5p 表达水平与老年卒中后抑郁的关系.方法 选取2018年2月至2020年10月胶州中心医院收治的129例老年卒中患者为研究组,另选取110名同期健康体检者为对照组,均检测血清miR-92a-1-5p、miR-92a-2...     

Interleukin‐35 regulates the balance of Th17 and Treg responses during the pathogenesis of connective tissue diseases

Interleukin (IL)‐35 belongs to the IL‐12 cytokine family and is a heterodimer of the p35 and Epstein‐Barr virus‐induced gene 3 (EBI3) subunits. Functionally, IL‐35 can promote the proliferation and activation of regulatory T cells (Tregs) and suppress the function of T helper 17 (Th17) cells and other inflammatory cells to inhibit immune responses. In recent years, an abnormal IL‐35 expression causing a Th17/Treg imbalance has been associated with the development and progression of several connective tissue diseases (CTDs), such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), dermatomyositis (DM)/polymyositis (PM), and primary Sjögren’s syndrome (pSS). Here, we review the role of IL‐35 in regulating the balance of Th17/Treg responses in different types of CTDs and provide new insights into the role of IL‐35 in these diseases.     

Th1 and Th17 immune responses to viable Propionibacterium acnes in patients with sarcoidosis

BackgroundPropionibacterium acnes and Mycobacterium tuberculosis have emerged as probable candidates responsible for sarcoidosis. This study was conducted to investigate the Th1/Th17 responses elicited by these pathogens in sarcoidosis and to clarify the causative role of these pathogens.MethodsPeripheral blood mononuclear cells (PBMCs) obtained from patients with sarcoidosis and from healthy volunteers were, respectively, co-cultured with viable P. acnes, with Bacille de Calmette et Guérin (BCG) as a viable M. tuberculosis complex, and with the early secretory antigenic target (ESAT)-6. Th1 cytokine production was measured using RT-PCR and enzyme-linked immunospot (ELISPOT) assays, and interleukin (IL)-17 mRNA expression was measured by RT-PCR.ResultsIL-2 secretion from PBMCs after stimulation with P. acnes was significantly higher in patients with sarcoidosis than in the controls. Similarly, IL-2 and IL-12 mRNA expression after stimulation with P. acnes was significantly higher in PBMCs from patients with sarcoidosis than in PBMCs from controls. In contrast, IL-17 mRNA expression was significantly lower in PBMCs from patients with sarcoidosis than in PBMCs from controls. No significant differences between the groups were observed in the responses to stimulation with BCG or ESAT-6.ConclusionSarcoidosis may arise from an imbalance of Th1/Th17 immune responses against viable P. acnes, but not M. tuberculosis complex.     

Th17/Treg在支气管哮喘发病机制中的作用及研究进展

Th17/Treg的提出突破了经典理论Th1/Th2失衡的局限性,IL-17、IL-10在支气管哮喘(简称哮喘)中的发生发展已经引起高度关注,然而基于它们之间在哮喘发病机制中缺乏深度和系统性,本文就Th17/Treg细胞及其它们的主要相关因子IL-17、IL-10、中性粒细胞与哮喘关系的研究进展作一简要综述.     

Th17/Treg在支气管哮喘发病机制中的作用及研究进展

Th17/Treg的提出突破了经典理论Th1/Th2失衡的局限性,IL-17、IL-10在支气管哮喘(简称哮喘)中的发生发展已经引起高度关注,然而基于它们之间在哮喘发病机制中缺乏深度和系统性,本文就Th17/Treg细胞及其它们的主要相关因子IL-17、IL-10、中性粒细胞与哮喘关系的研究进展作一简要综述.     

Tear osteopontin level and its relationship with local Th1/Th2/Th17/Treg cytokines in children with allergic conjunctivitis

Background

Allergic conjunctivitis (AC) is one of the most common allergic ocular diseases worldwide. Osteopontin (OPN), as a recently described Th2 inflammation related protein, may play a role in the pathogenesis of AC. The aim of this study was to identify the expression of OPN in children with AC.

Assessment of Th17/Treg cells and Th cytokines in an improved immune thrombocytopenia mouse model

Objectives: The improved passive immune thrombocytopenia (ITP) mouse model has been extensively utilized for the study of ITP. However, how closely this model matches the human inflammation state and immune background is unclear. Our study aimed to explore the profile of Th cytokines and Th17/Treg cells in the model.

Methods: We induced the ITP mouse model by dose-escalation injection of MWReg30. The serum levels of cytokines (IFN-γ, IL-2, IL-4, IL-10, IL-17A, and TGF-β1) were measured by enzyme-linked immunosorbent assay and the frequency of Th17 and Treg cells was measured by flow cytometry. The mRNA expression of Foxp3 and RORrt was measured by real-time PCR.

Results: The serum levels of cytokines IFN-γ, TGF-β1, IL-4, and IL-10 were significantly lower in ITP mice. The secretion of serum proinflammatory cytokines IL-2 and IL-17A and the percentage of Th17 cells showed no statistically significant increase. In ITP mice the frequency of Treg cells and mRNA expression of Foxp3 was significantly lower in splenocytes.

Conclusion: Our data suggest that the improved passive ITP mouse model does not mimic the autoimmune inflammatory process of human ITP. Compared with human ITP, this model has a similar change in frequency of Treg cells, which may directly or indirectly result from antibody-mediated platelet destruction due to attenuated release of TGF-β.     

Absence of donor Th17 leads to augmented Th1 differentiation and exacerbated acute graft-versus-host disease

Th17 is a newly identified T-cell lineage that secretes proinflammatory cytokine IL-17. Th17 cells have been shown to play a critical role in mediating autoimmune diseases such as EAE, colitis, and arthritis, but their role in the pathogenesis of graft-versus-host disease (GVHD) is still unknown. Here we showed that, in an acute GVHD model of C57BL/6 (H-2(b)) donor to BALB/c (H-2(d)) recipient, IL-17(-/-) donor T cells manifested an augmented Th1 differentiation and IFN-gamma production and induced exacerbated acute GVHD. Severe tissue damage mediated by IL-17(-/-) donor T cells was associated with increased Th1 infiltration, up-regulation of chemokine receptors by donor T cells, and enhanced tissue expression of inflammatory chemokines. Administration of recombinant IL-17 and neutralizing IFN-gamma in the recipients given IL-17(-/-) donor cells ameliorated the acute GVHD. Furthermore, the regulation of Th1 differentiation by IL-17 or Th17 may be through its influence on host DCs. Our results indicate that donor Th17 cells can down-regulate Th1 differentiation and ameliorate acute GVHD in allogeneic recipients, and that treatments neutralizing proinflammatory cytokine IL-17 may augment acute GVHD as well as other inflammatory autoimmune diseases.     

参麦注射液对支气管哮喘患者外周血Th17/Treg细胞的影响

目的 探讨参麦注射液对支气管哮喘(简称哮喘)患者外周血Th17/Treg细胞的影响及其意义.方法 选取山西医科大学第一医院呼吸科急性发作期、缓解期哮喘患者各25例,选取山西医科大学第一医院体检中心肺功能正常、激发或者舒张试验阴性的健康人25例作为对照组,分别使用1640培养液及参麦注射液进行干预处理.抽取晨起空腹静脉血5 ml,运用流式细胞仪对各组外周血Th17细胞、Treg细胞分别占CD4+的比例及Th17/Trcg细胞的比值进行比较,同时检测血清中IL-10因子的水平.结果 ①各组间干预前CD4+ Th17细胞/CD4+T细胞、CD4+ Th17细胞/CD4+ Treg细胞的比值,急性发作期组(3.05±1.27、1.49±1.78)高于缓解期组(2.38±0.93、0.61±0.24)及对照组(1.19±0.39、0.30±1.14),差异有统计学意义(P＜0.05),缓解期高于对照组,差异有统计学意义(P＜0.05);CD4+Treg细胞/CD4+T细胞的比值,对照组(5.20±3.26)高于缓解期组(3.99±0.90)及急性发作期组(2.76±0.93),差异有统计学意义,(P＜0.05),缓解期组高于急性发作期组,差异有统计学意义(P ＜0.05).血清中IL-10因子的水平,对照组(5,28±1.31)高于缓解期组(4.46±0.83)及急性发作期组(3.90±0.64),差异有统计学意义(P＜0.05),缓解期组高于急性发作期组,差异有统计学意义(P ＜0.05).②同一组间CD4+ Th17细胞/CD4+T细胞、CD4+Th17细胞/CD4+ Treg细胞的比值,干预前高于干预后,差异有统计学意义(P＜0.05).CD4+ Treg细胞/CD4+T细胞的比值,干预后高于干预前,差异有统计学意义(P＜0.05).血清中IL-10因子水平,干预后高于干预前,差异有统计学意义(P ＜0.05).结论 哮喘患者外周血中存在Th17/Treg细胞失衡,参麦注射液可以改善哮喘患者的Th17/Treg细胞失衡.     

Treg和Th17细胞在寄生虫感染和卫生假说中的免疫调节

寄生虫感染在发展中国家仍然是一个严重威胁人类健康、影响社会经济发展的公共卫生问题。近年来,随着分子生物学和免疫学等研究进展,人们对寄生虫感染的免疫防御反应及免疫病理机制有了更多认识。CD4~+T细胞在机体免疫防御及免疫调节中发挥着非常重要的作用。传统上认为CD4~+T细胞在体内外可分化成Th1、Th2两大细胞亚群,它们产生不同的细胞因子,发挥不同功能。后来又发现了两种新的CD4~+T细胞亚群,即Th17细胞和调节性T(Treg)细胞。它们具有与传统的Th1、Th2细胞完全不同的、独立的分化和调节机制。已有大量研究证实,Treg和Th17细胞在寄生虫病的抗虫免疫及免疫病理机制中发挥着重要作用。此外,Th17和Treg细胞在寄生虫感染所诱导的卫生假说中的作用越来越受到重视。本文根据当前国内外有关Treg和Th17细胞分化及功能的研究进展,对Treg和Th17细胞在寄生虫感染及卫生假说中的作用作一简要综述。