Is Ewing's Sarcoma a Stem Cell Tumor?

Solving the histogenesis of Ewing's sarcoma has defied investigators despite progress in understanding its molecular pathogenesis. In a recent issue of Cancer Cell, Tirode et al. (2007) present evidence supporting the hypothesis that this rare cancer arises from a primitive mesenchymal precursor.     

Cell Stem Cell揭示受精卵DNA去甲基化重要机制

<正>2014年9月11日,Cell Stem Cell在线发表了中国科学院上海生科院生物化学与细胞生物学研究所徐国良研究组、李劲松研究组和北京大学生命科学学院生物动态光学成像中心汤富酬研究组的最新研究成果,该研究发现小鼠早期胚胎中母源和父源基因组在单细胞的受精卵阶段均会发生大规模的DNA主动和被动去甲基化,并且DNA双加氧酶Tet3介导了主动去甲基化的发生,而糖苷酶     

A Special Issue on Stem Cell Research

Stem cells possess the remarkable ability of extensive self-renewal and differentiation into specific celllineages,and they play essential roles in development and adult tissue homeostasis.Due to their criticalimportance in normal physiology and the promise for use in regenerative medicine to treat a variety ofdiseases,stem cells have attracted extensive research interest in recent years.As China's premium in-ternational journal with a broad scope in cell and molecular biology,Cell Research has witnessed moreand more submissions on stem cell research.Indeed,along with the traditional strengths of the journal inmolecular immunology,cancer biology,and plant molecular physiology,stem cell research has graduallyand naturally evolved into a new growth point of Cell Research.Reflecting the growing interest of bothour readers and authors in this exciting and expanding field,we are pleased to present this Special Issueon Stem Cell Research.     

Cell Stem Cell发表原始多潜能干细胞的最新研究成果

<正>2014年10月2日,Cell Stem Cell刊登了北京大学生命科学学院邓宏魁研究组最新研究成果。该研究在世界上首次成功将恒河猴皮肤细胞诱导成为了"原始多潜能干细胞",是干细胞领域的一项重要突破。北京大学生命科学学院邓宏魁研究团队早在2009年在国际上首次建立传统的恒河猴诱导多能干细胞(iPS细胞),在这个研究基础上,他们发现一些关键信号通路的调控因子,将恒河猴的传统     

Cancer: Inappropriate Expression of Stem Cell Programs?

Cancer stem cells (CSCs) are a subpopulation of cancer cells that possess characteristics, including self-renewal, associated with normal stem cells. In this issue of Cell Stem Cell, Wong et al. (2008) define a core embryonic stem cell (ESC)-like gene expression program that may be important for CSC function in multiple epithelial cancers.     

Quantification of Biomass and Cell Motion in Human Pluripotent Stem?Cell?Colonies

Somatic cell reprogramming to pluripotency requires an immediate increase in cell proliferation and reduction in cell size. It is unknown whether proliferation and biomass controls are similarly coordinated with early events during the differentiation of pluripotent stem cells (PSCs). This impasse exists because PSCs grow in tight clusters or colonies, precluding most quantifying approaches. Here, we investigate live cell interferometry as an approach to quantify the biomass and growth of HSF1 human PSC colonies before and during retinoic acid-induced differentiation. We also provide an approach for measuring the rate and coordination of intracolony mass redistribution in HSF1 clusters using live cell interferometry images. We show that HSF1 cells grow at a consistent, exponential rate regardless of colony size and display coordinated intracolony movement that ceases with the onset of differentiation. By contrast, growth and proliferation rates show a decrease of only ∼15% decrease during early differentiation despite global changes in gene expression and previously reported changes in energy metabolism. Overall, these results suggest that cell biomass and proliferation are regulated independent of pluripotency during early differentiation, which is distinct from what occurs with successful reprogramming.     

Human Parthenogenetic Embryonic Stem Cell–Derived Neural Stem Cells Express HLA-G and Show Unique Resistance to NK Cell–Mediated Killing

Parent-of-origin imprints have been implicated in the regulation of neural differentiation and brain development. Previously we have shown that, despite the lack of a paternal genome, human parthenogenetic (PG) embryonic stem cells (hESCs) can form proliferating neural stem cells (NSCs) that are capable of differentiation into physiologically functional neurons while maintaining allele-specific expression of imprinted genes. Since biparental (“normal”) hESC–derived NSCs (N NSCs) are targeted by immune cells, we characterized the immunogenicity of PG NSCs. Flow cytometry and immunocytochemistry revealed that both N NSCs and PG NSCs exhibited surface expression of human leukocyte antigen (HLA) class I but not HLA-DR molecules. Functional analyses using an in vitro mixed lymphocyte reaction assay resulted in less proliferation of peripheral blood mononuclear cells (PBMC) with PG compared with N NSCs. In addition, natural killer (NK) cells cytolyzed PG less than N NSCs. At a molecular level, expression analyses of immune regulatory factors revealed higher HLA-G levels in PG compared with N NSCs. In line with this finding, MIR152, which represses HLA-G expression, is less transcribed in PG compared with N cells. Blockage of HLA-G receptors ILT2 and KIR2DL4 on natural killer cell leukemia (NKL) cells increased cytolysis of PG NSCs. Together this indicates that PG NSCs have unique immunological properties due to elevated HLA-G expression.     

Cell Stem Cell:线粒体DNA突变潜藏于人诱导性多能干细胞中

正在一项新的研究中,美国俄勒冈健康与科学大学(OHSU)胚胎细胞与基因治疗中心主任Shoukhrat Mitalipov博士及其研究团队首次证实一个存在已久的假设:当变老时,基因突变积累在人们的线粒体(即细胞能量工厂)中。研究人员发现作为一类对病人的皮肤细胞或血细胞进行重编程而产生的干细胞,诱导性多能干细胞(iPS细胞)含有存在缺陷的线粒体DNA。相关研究结果在     

Cell Stem Cell:线粒体DNA突变潜藏于人诱导性多能干细胞中

正在一项新的研究中,美国俄勒冈健康与科学大学(OHSU)胚胎细胞与基因治疗中心主任Shoukhrat Mitalipov博士及其研究团队首次证实一个存在已久的假设:当变老时,基因突变积累在人们的线粒体(即细胞能量工厂)中。研究人员发现作为一类对病人的皮肤细胞或血细胞进行重编程而产生的干细胞,诱导性多能干细胞(iPS细胞)含有存在缺陷的线粒体DNA。相关研究结果在线发表在Cell Stem Cell期刊上。     

Meeting Announcement 2007 Shanghai International Symposium on Stem Cell Research

We are delighted to announce an international symposium on stem cell research to be held in Shanghai on November 6-9, 2007. This meeting is co-organized by Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and several other research institutions in China, together with the International Society for Stem Cell Research （ISSCR）. This is the first time ISSCR co-organizes a meeting with other organizations. ISSCR will organize a delegacy of 8-10 members to participate the symposium.[第一段]     

Proliferating Patent Problems with Human Embryonic Stem Cell Research?

The scientific challenges and ethical controversies facing human embryonic stem cell (hESC) research continue to command attention. The issues posed by patenting hESC technologies have, however, largely failed to penetrate the discourse, much less result in political action. This paper examines U.S. and European patent systems, illustrating discrepancies in the patentability of hESC technologies and identifying potential negative consequences associated with efforts to make available hESC research tools for basic research purposes while at same time strengthening the position of certain patent-holders' rights. Differences between the U.S. and the European contexts may in part explain why the course of hESC research in those jurisdictions ultimately diverges. Nevertheless, questions about whether and how patenting, related agreements, and licensing practices progress and shape the field of hESC research in both the U.S., Europe, and elsewhere must no longer be marginalised. These questions are fundamentally important in determining what benefits are likely to result from hESC research. Assuring these benefits is the moral issue with which patent systems are most intrinsically concerned, and that governments must begin to directly address rather than assume or ignore.     

Cell Stem Cell:研究开发出在体外长期培养成体干细胞的方法

正在一项新的研究中,来自美国麻省总医院(MGH)等机构的研究人员开发出的一种新方法可能引发成体干细胞培养领域变革。研究人员描述了获得来自在日常治疗肺部疾病期间收集的各种组织样品中的气道干细胞(airway stem cell),并对它们进行增殖。这种方法似乎也可用于几种其他的组织,如皮肤、胃肠道内壁和生殖道。相关研究结果在线发表在Cell Stem Cell期刊上。     

Stem Cell Epigenetics: Is It All Downhill from Here?

In this issue of Cell Stem Cell, Fasano et al. (2007) investigate the role of Bmi-1 in neural stem cells in vitro and in vivo. They find a progressively increasing requirement for Bmi-1 function in stem cells during development that, surprisingly, seems to involve regulation of the cell-cycle inhibitor p21.     

Cell Stem Cell:sox9调节皮肤癌细胞自我更新促进肿瘤转移和侵袭

<正>近日,来自比利时的科学家在国际学术期刊cell stem cell发表了一项最新研究进展,他们发现转录因子sox9在基底细胞癌形成和侵袭过程中发挥重要作用,除此之外,sox9还能够促进基底细胞癌干性维持和自我更新,因此sox9可能是基底细胞癌治疗的一个重要靶点。Sox9是一个在许多实体肿瘤中发生异常表达的转录因子,但一直以来对sox9在肿瘤发生中所发挥的重要作用了解较少。在该项研究中,研     

Why Myc? An Unexpected Ingredient in the Stem Cell Cocktail

Screening cocktails of candidate genes for induction of pluripotency and self-renewal in nonstem cells has identified a surprising new embryonic stem cell regulator, the myc proto-oncogene. Here the possible mechanisms by which myc controls self-renewal and pluripotency are discussed.     

European Stem Cell Patents: Taking the Moral High Road?

A European law that prevents the patenting of discoveries that contravene morality is causing confusion when it comes to human embryonic stem cells. The ensuing debate is markedly different from the one in the United States, where the scope of stem cell patents and their licensing are under challenge.     

Restoring Stem Cell Function in Aged Tissues by Direct Reprogramming?

Adult stem cells are responsible for the cellular turnover of many organs, and an impairment in their function leads to aging and disease. In efforts to reverse the process of tissue stem cell aging, we speculate on the promise and challenges of in vivo direct reprogramming strategies.