Invasive prostate cancer cells are tumor initiating cells that have a stem cell-like genomic signature

Development of metastasis is a leading cause of cancer-induced death. Acquisition of an invasive tumor cell phenotype suggests loss of cell adhesion and basement membrane breakdown during a process termed epithelial-to-mesenchymal transition (EMT). Recently, cancer stem cells (CSC) were discovered to mediate solid tumor initiation and progression. Prostate CSCs are a subpopulation of CD44⁺ cells within the tumor that give rise to differentiated tumor cells and also self-renew. Using both primary and established prostate cancer cell lines, we tested the assumption that CSCs are more invasive. The ability of unsorted cells and CD44-positve and -negative subpopulations to undergo Matrigel invasion and EMT was evaluated, and the gene expression profiles of these cells were analyzed by microarray and a subset confirmed using QRT-PCR. Our data reveal that a subpopulation of CD44⁺ CSC-like cells invade Matrigel through an EMT, while in contrast, CD44⁻ cells are non-invasive. Furthermore, the genomic profile of the invasive cells closely resembles that of CD44⁺CD24⁻ prostate CSCs and shows evidence for increased Hedgehog signaling. Finally, invasive cells from DU145 and primary prostate cancer cells are more tumorigenic in NOD/SCID mice compared with non-invasive cells. Our data strongly suggest that basement membrane invasion, an early and necessary step in metastasis development, is mediated by these potential cancer stem cells. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Th17细胞在子痫前期患者外周血表达增加

观察正常妊娠妇女和子痫前期疾病患者外周血CD4+T细胞中Th17细胞和特异性转录因子维A酸相关孤独受体(retinoid-related orphan nuclear receptor,RORγt)的表达和意义。实验组为子痫前期疾病患者25例,正常妊娠妇女20例,未孕妇女20例。采集研究对象外周血,酶联免疫吸附试验(ELISA)检测Th17细胞相关细胞因子IL-17A,IL-6,TNF-α的表达,Ficoll法分离外周血单个核细胞(PBMC),免疫磁珠分选CD4+T淋巴细胞,逆转录-聚合酶联反应(RT-RCR)半定量检测CD4+T细胞中Th17细胞特异性转录因子RORγt的表达,流式细胞术检测CD4+IL-17+T细胞比例。子痫前期患者外周血清中IL-6、IL-17A的含量分别为(31.72±13.34)ng/L、(2.61±1.64)ng/L,高于正常妊娠组水平,差异有显著统计学意义(P<0.01),TNF-α在子二组间的表达分别为(18.00±8.64)ng/L和(11.69±3.68)ng/L,差异有统计学意义(P<0.05);RORγt mRNA在子痫前期组的表达高于正常妊娠组,净光密度值差异有显著统计学差异(P<0.01),CD4+IL-17+T细胞在子痫前期组的表达为(1.83±0.42)%,高于正常妊娠组(0.87±0.26)%,差异有显著统计学意义(P<0.01)。子痫前期患者外周血CD4+T细胞中RORγt mRNA、Th17细胞以及Th17细胞相关细胞因子表达异常,可能在疾病的发病机理中起到重要作用。     

脂肪源性干细胞对多发性硬化患者Th17的免疫调控作用

 目的: 探讨人脂肪源性干细胞(hASCs)对多发性硬化(MS)患者外周血辅助性T细胞17(Th17)的免疫调控作用机制。方法: 分离、纯化脂肪组织中的hASCs。采用密度梯度离心法分离MS患者外周血单个核细胞(PBMCs),磁珠分选CD4⁺T细胞,体外刺激细胞向Th17极化,并加入不同比例的hASCs(hASCs:CD4⁺T为1:4和1:10)共培养4 d,设立添加anti-LIF抗体组;流式细胞术检测共培养后Th17细胞占CD4⁺T细胞的比例,real-time PCR检测白细胞介素6受体(IL-6R)、白细胞介素23受体(IL-23R)、白血病抑制因子受体(LIFR)、维甲酸相关孤儿受体γt(RORγt)及白血病抑制因子(LIF)的mRNA水平变化;ELISA法检测共培养体系上清液中LIF的水平。结果: 分离的hASCs经流式细胞术鉴定可基本判定为hASCs;PBMCs经磁珠法分选后获得90%以上纯度的CD4⁺T细胞。共培养后,1:4组和1:10组中Th17细胞所占比例下降,且存在高浓度抑制效应;共培养后RORγt、IL-6R和IL-23R的mRNA表达水平下降,LIFR和LIF的mRNA表达水平均升高;加入anti-LIF抗体后,Th17细胞比例回升至对照组水平;RORγt和IL-6R的mRNA表达水平回升;ELISA检测各组LIF的水平,共培养组LIF分泌均较对照组明显增多,加入anti-LIF抗体后明显减少。结论: hASCs可抑制MS患者Th17细胞的分化,其作用可能与其分泌LIF、通过IL-6/LIF轴竞争性抑制有关。     

Mouse neutrophils are professional antigen-presenting cells programmed to instruct Th1 and Th17 T-cell differentiation

Neutrophils play a major role in the innate immune system and are normally considered to be short-lived effector cells that exert anti-microbial activity and sometimes immunopathology. Here, we show that these cells possess an additional function as professional antigen-presenting cells capable of priming a T(h)1- and T(h)17-acquired immune response. Using flow cytometry, fluorescence microscopy and western blotting, we show that mouse neutrophils express MHC class II and co-stimulatory molecules CD80 and CD86 after T-cell co-incubation. Neutrophils pulsed with ovalbumin (OVA) process and present peptide antigen to OVA-specific T cells in an MHC class II-dependent manner. Importantly, we demonstrate that neutrophils can prime antigen-specific T(h)1 and T(h)17 immune responses even without the addition of exogenous cytokines to cell cultures.     

胚胎骨髓来源间充质干细胞对人Th17细胞的免疫调节

背景：众多研究表明间充质干细胞能发挥免疫调节功能,抑制T细胞增殖。 目的：观察胚胎骨髓来源间充质干细胞对人Th17细胞的调节作用。 方法：将人胚胎骨髓间充质干细胞与正常人外周血单个核细胞或CD4⁺ T细胞以1∶10比例共培养4 d,以单个核细胞或CD4⁺T细胞单独培养为对照。应用实时定量PCR检测细胞白细胞介素17 mRNA表达,酶联免疫吸附试验检测细胞上清中白细胞介素17蛋白水平,流式细胞术检测Th17细胞数量。 结果与结论：胚胎骨髓来源间充质干细胞与单个核细胞共培养组白细胞介素17 mRNA表达水平明显高于单个核细胞组(P < 0.01)。与此一致的是,胚胎骨髓来源间充质干细胞与单个核细胞或CD4⁺T细胞共培养组细胞上清中白细胞介素17蛋白水平明显高于单个核细胞组、CD4⁺ T细胞组(P < 0.05,P < 0.01)。胚胎骨髓来源间充质干细胞与CD4⁺ T细胞共培养组Th17细胞数量明显高于CD4⁺ T细胞组(P < 0.01),但胚胎骨髓来源间充质干细胞本身并不表达白细胞介素17。表明胚胎骨髓来源间充质干细胞可促进人Th17细胞增殖。     

Th17细胞与自身免疫性疾病

Th17细胞是近年发现的不同于Th1细胞和Th2细胞的新型CD4^＋T细胞亚群。活化的Th17细胞可分泌IL—17、肿瘤坏死因子-α（TNF—α）、IL-6、粒-单核细胞集落刺激因子（GM—CSF）等多种促炎症因子,Th17细胞不适当的激活与多种自身免疫性疾病和过敏性疾病密切相关。在体内阻断Th17细胞的分化、扩增及其相关细胞因子可预防、延缓或阻止自身免疫性疾病的发生、发展。     

Human Th17 cells: Are they different from murine Th17 cells?

Type 17 Th (Th17) cells have been identified as a distinct population of CD4⁺ effector T cells different from Th1 and Th2 cells. While the pre‐eminent cytokine of Th1 cells is IFN‐γ and that of Th2 cells is IL‐4, the distinctive cytokine of Th17 cells is IL‐17A. However, although murine and human Th1 and Th2 cells exhibit strong similarities, human and murine Th17 cells seem to differ in several aspects.     

Elevated levels of Th17 cells and Th17-related cytokines are associated with disease activity in patients with inflammatory bowel disease

Objective

Interleukin-17(IL-17)-producing T helper(Th)17 cells are considered as a new subset of cells critical to the development of inflammatory bowel disease (IBD). We aimed to investigate the distribution of Th17 cells, the expressions of Th17-related cytokines (IL-17, IL-21 and IL-22) and their association with disease activity in IBD patients.

Methods

We collected intestinal tissue biopsies from 40 patients with active ulcerative colitis (UC), 20 patients with active Crohn’s disease (CD) and 20 healthy controls. The distribution of Th17 cells and expressions of Th17-related cytokines in colonic tissues were evaluated by a standard immunohistochemical procedure. Serum IL-17, IL-21 and IL-22 levels were determined by ELISA. Pearson’s and Spearman’s correlation analyses were performed to analyze the correlation between the number of Th17 cells, the expressions of Th17-related cytokines and disease activity index, endoscopic and histological grading, and CRP and PLT levels, respectively.

Results

Compared with healthy controls, the number of Th17 cells and the expressions of IL-17, IL-21 and IL-22 were significantly increased in active IBD patients (P < 0.05). In addition, Pearson’s and Spearman’s correlation analyses showed that the number of Th17 cells and the expressions of Th17-related cytokines were correlated with disease activity index, endoscopic and histological grading, CRP and PLT levels (P < 0.05).

Conclusions

Th17 cells and Th17-related cytokines (IL-17, IL-21 and IL-22) were increased in the intestinal mucosa in active IBD patients and may play an important role in disease activity and mucosal damage.     

Th17 cell differentiation: the long and winding road

The characterization of the new lineage of IL-17-producing CD4+ T helper (Th17) cells has revolutionized our current understanding of T cell-mediated immunity. Over the past five years, there have been many twists and turns as the pathways that lead to Th17 cell differentiation have been elucidated. Not least of these was the discovery that TGF-beta is a crucial cytokine for Th17 cell development, suggesting that Th17 and regulatory T cell subsets share reciprocal developmental pathways during the pathogenesis or control of inflammation. This review aims to bring together the observations that have formed current opinion on factors that promote and contain Th17 cell development, in both mouse and man. Unresolved controversies in this field are also discussed: For example, IL-23 is absolutely required for disease pathogenesis in many models of Th17-cell-mediated autoimmunity, yet its role in Th17 cell development is relatively unclear.     

Human embryonic stem cells have a unique epigenetic signature

Human embryonic stem (hES) cells originate during an embryonic period of active epigenetic remodeling. DNA methylation patterns are likely to be critical for their self-renewal and pluripotence. We compared the DNA methylation status of 1536 CpG sites (from 371 genes) in 14 independently isolated hES cell lines with five other cell types: 24 cancer cell lines, four adult stem cell populations, four lymphoblastoid cell lines, five normal human tissues, and an embryonal carcinoma cell line. We found that the DNA methylation profile clearly distinguished the hES cells from all of the other cell types. A subset of 49 CpG sites from 40 genes contributed most to the differences among cell types. Another set of 25 sites from 23 genes distinguished hES cells from normal differentiated cells and can be used as biomarkers to monitor differentiation. Our results indicate that hES cells have a unique epigenetic signature that may contribute to their developmental potential.     

Th17 cells in inflammation and autoimmunity

T helper 17 (Th17), a distinct subset of CD4⁺ T cells with IL-17 as their major cytokine, orchestrate the pathogenesis of inflammatory and autoimmune diseases. Dysregulated Th17 cells contribute to inflammatory and autoimmune diseases. Candidate biologics are in development for targeting IL-17, IL-17 receptors or IL-17 pathways. Several drugs that impact the IL-17 pathway are already in clinical trials for the treatment of autoimmune diseases. In this review we provide evidence for the role of Th17 cells in immune-mediated diseases. An understanding of the role of Th17 in these conditions will provide important insights and unravel novel targets for therapeutic intervention.     

Th17 cells in human disease

Summary: Our understanding of the role of T cells in human disease is undergoing revision as a result of the discovery of T-helper 17 (Th17) cells, a unique CD4⁺ T-cell subset characterized by production of interleukin-17 (IL-17). IL-17 is a highly inflammatory cytokine with robust effects on stromal cells in many tissues. Recent data in humans and mice suggest that Th17 cells play an important role in the pathogenesis of a diverse group of immune-mediated diseases, including psoriasis, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and asthma. Initial reports also propose a role for Th17 cells in tumorigenesis and transplant rejection. Important differences, as well as many similarities, are emerging when the biology of Th17 cells in the mouse is compared with corresponding phenomena in humans. As our understanding of human Th17 biology grows, the mechanisms underlying many diseases are becoming more apparent, resulting in a new appreciation for both previously known and more recently discovered cytokines, chemokines, and feedback mechanisms. Given the strong association between excessive Th17 activity and human disease, new therapeutic approaches targeting Th17 cells are highly promising, but the potential safety of such treatments may be limited by the role of these cells in normal host defenses against infection.     

Role of Th1 and Th17 cells in organ-specific autoimmunity

CD4(+) IFN-gamma-producing Th1 cells have long been associated with the pathogenesis of many organ-specific autoimmune diseases; however, the observation of disease in mice deficient in molecules involved in Th1 cell differentiation raised the possibility that other effector T cells were responsible for inducing autoimmunity. Recently, a new CD4(+) effector T cell subset that produces IL-17 (Th17) has emerged. The fact that Th17 cells are highly auto-pathogenic has fueled a debate as to what role, if any, Th1 cells play in the induction of tissue inflammation and autoimmune disease. This review will discuss the respective roles of the Th1 and Th17 subsets in organ-specific autoimmunity.