Medical and Biomedical Researches

Interspecies Nuclear Transfer: Implications for Embryonic Stem Cell Biology.

March 29th, 2008
Interspecies Nuclear Transfer: Implications for Embryonic Stem Cell Biology. Accessibility of human oocytes for research poses a serious ethical challenge to society. This fact categorically holds true when pursuing some of the most promising areas of research, such as somatic cell nuclear transfer and embryonic stem ...

Posted in researches 3 | No Comments »

Evaluating Therapeutic Efficacy against Cancer Stem Cells: New Challenges Posed by a New Paradigm.

March 29th, 2008
Evaluating Therapeutic Efficacy against Cancer Stem Cells: New Challenges Posed by a New Paradigm. Current measures of anticancer drug efficacy reflect bulk cell killing and are poorly suited to detect activity against cancer stem cells (CSCs), which sustain tumor growth. The CSC paradigm necessitates a reexamination ...

Posted in researches 3 | No Comments »

The Generation of Six Clinical-Grade Human Embryonic Stem Cell Lines.

March 29th, 2008
The Generation of Six Clinical-Grade Human Embryonic Stem Cell Lines. The edict for producing clinically compliant human embryonic stem cells (hESCs) necessitates adherence to global ethical standards for egg procurement and embryo donation, conformity to regulations controlling clinical-grade cell and tissue product development, and compliance with ...

Posted in researches 3 | No Comments »

The Epigenetics of Fragile X Syndrome.

March 29th, 2008
The Epigenetics of Fragile X Syndrome. In this issue of Cell Stem Cell, Eiges et al. (2007) generate a human ES cell line from an embryo identified by preimplantation genetic diagnosis, and shed light on the molecular pathology of fragile X syndrome. The discovery that, upon ...

Posted in researches 3 | No Comments »

Moving Forward in Human Mammary Stem Cell Biology and Breast Cancer Prognostication Using ALDH1.

March 29th, 2008
Moving Forward in Human Mammary Stem Cell Biology and Breast Cancer Prognostication Using ALDH1. In this issue of Cell Stem Cell, the seminal work of Ginestier et al. (2007) elegantly demonstrates that aldehyde dehydrogenase 1 (ALDH1) facilitates the identification and isolation of normal and malignant human ...

Posted in researches 3 | No Comments »

The Endosteum Region Keeps Human Leukemic Stem Cells Alive.

March 29th, 2008
The Endosteum Region Keeps Human Leukemic Stem Cells Alive. Only a subset of hierarchically arranged, primitive human AML progenitor cells can initiate the disease in transplanted immune-deficient mice. A publication in Nature Biotechnology by Ishikawa et al. (2007) describes a new animal model to study chemotherapy-resistant, ...

Posted in researches 3 | No Comments »

Kinship and Descent: Redefining the Stem Cell Compartment in the Adult Hippocampus.

March 29th, 2008
Kinship and Descent: Redefining the Stem Cell Compartment in the Adult Hippocampus. Identifying multipotent, self-renewing neural stem cells (NSCs) within the adult hippocampus in vivo has been somewhat elusive. In this issue of Cell Stem Cell, Suh et al. (2007) show that Sox2-expressing cells in the ...

Posted in researches 3 | No Comments »

Asymmetric Cell Division in Normal and Malignant Hematopoietic Precursor Cells.

March 29th, 2008
Asymmetric Cell Division in Normal and Malignant Hematopoietic Precursor Cells. Hematopoietic precursors have long been postulated to divide in an asymmetric manner. In this issue of Cell Stem Cell, Wu et al. (2007) provide evidence for the existence of asymmetric cell division and its possible molecular ...

Posted in researches 3 | No Comments »

Decline in self-renewal factors contributes to aging of the stem cell niche in the Drosophila testis

March 29th, 2008
Decline in self-renewal factors contributes to aging of the stem cell niche in the Drosophila testis. Aging is characterized by compromised organ and tissue function. A decrease in stem cell number and/or activity could lead to the aging-related decline in tissue homeostasis. We have analyzed how ...

Posted in researches 3 | No Comments »

Stem cell aging is controlled both intrinsically and extrinsically in the Drosophila ovary.

March 29th, 2008
Stem cell aging is controlled both intrinsically and extrinsically in the Drosophila ovary. It is widely postulated that tissue aging could be, at least partially, caused by reduction of stem cell number, activity, or both. However, the mechanisms of controlling stem cell aging remain largely a ...

Posted in researches 3 | No Comments »

Neurofibromatosis-1 Regulates Neuronal and Glial Cell Differentiation from Neuroglial Progenitors In

March 29th, 2008
Neurofibromatosis-1 Regulates Neuronal and Glial Cell Differentiation from Neuroglial Progenitors In Vivo by Both cAMP- and Ras-Dependent Mechanisms. Individuals with neurofibromatosis type 1 (NF1) develop abnormalities of both neuronal and glial cell lineages, suggesting that the NF1 protein neurofibromin is an essential regulator of neuroglial progenitor ...

Posted in researches 3 | No Comments »

Elucidation of the phenotypic, functional, and molecular topography of a myeloerythroid progenitor c

March 29th, 2008
Elucidation of the phenotypic, functional, and molecular topography of a myeloerythroid progenitor cell hierarchy. The major myeloid blood cell lineages are generated from hematopoietic stem cells by differentiation through a series of increasingly committed progenitor cells. Precise characterization of intermediate progenitors is important for understanding fundamental ...

Posted in researches 3 | No Comments »

Reciprocal Activation of GATA-1 and PU.1 Marks Initial Specification of Hematopoietic Stem Cells int

March 29th, 2008
Reciprocal Activation of GATA-1 and PU.1 Marks Initial Specification of Hematopoietic Stem Cells into Myeloerythroid and Myelolymphoid Lineages. A hierarchical hematopoietic development with myeloid versus lymphoid bifurcation has been proposed downstream of the multipotent progenitor (MPP) stage, based on prospective isolation of progenitors capable of generating ...

Posted in researches 3 | No Comments »

Colon cancer stem cells dictate tumor growth and resist cell death by production of interleukin-4.

March 29th, 2008
Colon cancer stem cells dictate tumor growth and resist cell death by production of interleukin-4. A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas ...

Posted in researches 3 | No Comments »

Sic transit gloria: farewell to the epidermal transit amplifying cell?

March 29th, 2008
Sic transit gloria: farewell to the epidermal transit amplifying cell? For the past 30 years, the prevailing model of epidermal homeostasis has been that epidermal stem cells give rise to transit amplifying cells, which undergo a limited number of cell divisions before initiating terminal differentiation. Recent ...

Posted in researches 3 | No Comments »

New Advances in iPS Cell Research Do Not Obviate the Need for Human Embryonic Stem Cells.

March 29th, 2008
New Advances in iPS Cell Research Do Not Obviate the Need for Human Embryonic Stem Cells. Recently three different studies were published demonstrating that mouse fibroblast (skin) cells can be directly reprogrammed to behave like embryonic stem cells (Okita et al., 2007; Wernig et al., 2007; ...

Posted in researches 3 | No Comments »

Oct4 and its pseudogenes confuse stem cell research.

March 29th, 2008
Oct4 and its pseudogenes confuse stem cell research. Octamer-binding transcription factor 4 (Oct4) encodes a POU-domain transcription factor (Scholer et al., 1990). The gene is specifically expressed in embryonic stem (ES) cells but can also be detected in adult stem cells such as bone marrow-derived mesenchymal ...

Posted in researches 3 | No Comments »

The missing niche for spermatogonial stem cells: do blood vessels point the way?

March 29th, 2008
The missing niche for spermatogonial stem cells: do blood vessels point the way? Although spermatogonial stem cell niches have been defined in lower organisms, their definitive localization in mammalian seminiferous tubules has been elusive. In a recent Science paper, Yoshida et al. (2007) elegantly demonstrated a ...

Posted in researches 3 | No Comments »

An Argument against a Role for Oct4 in Somatic Stem Cells.

March 29th, 2008
An Argument against a Role for Oct4 in Somatic Stem Cells. Reports of Oct4 expression in somatic and cancer cells have suggested that Oct4 could regulate self-renewal in somatic stem cells as it does in embryonic stem cells. In this issue of Cell Stem Cell, Lengner ...

Posted in researches 3 | No Comments »

Defining the pathways of early adult hematopoiesis.

March 29th, 2008
Defining the pathways of early adult hematopoiesis. The journeys that hematopoietic cells take to differentiate from long-term stem cells into committed cells have recently been a topic of debate. In this issue of Cell Stem Cell, Arinobu et al. (2007) and Pronk et al. (2007) provide ...

Posted in researches 3 | No Comments »

Quo vadis brain repair? A long axonal journey in the adult CNS.

March 29th, 2008
Quo vadis brain repair? A long axonal journey in the adult CNS. Recently in Nature Neuroscience, Gaillard et al. (2007) study axonal projections from embryonic cortical explants grafted into acutely damaged adult motor cortex. After attempting to rule out fusion of donor tissue with pre-existing host ...

Posted in researches 3 | No Comments »

Chemotherapy and cancer stem cells.

March 29th, 2008
Chemotherapy and cancer stem cells. Cancer stem cells are subsets of tumor cells defined through the capacity to initiate tumors and have been linked to therapeutic resistance. In this issue of Cell Stem Cell, Todaro et al. (2007) demonstrate that targeting tumor IL-4 sensitizes colon cancer ...

Posted in researches 3 | No Comments »

Recombination Signatures Distinguish Embryonic Stem Cells Derived by Parthenogenesis and Somatic Cel

March 29th, 2008
Recombination Signatures Distinguish Embryonic Stem Cells Derived by Parthenogenesis and Somatic Cell Nuclear Transfer. Parthenogenesis and somatic cell nuclear transfer (SCNT) are two methods for deriving embryonic stem (ES) cells that are genetically matched to the oocyte donor or somatic cell donor, respectively. Using genome-wide single ...

Posted in researches 3 | No Comments »

Mll has a critical role in fetal and adult hematopoietic stem cell self-renewal.

March 29th, 2008
Mll has a critical role in fetal and adult hematopoietic stem cell self-renewal. The Mixed Lineage Leukemia (Mll) gene is a homolog of Drosophila Trithorax commonly rearranged in infant leukemia. Comprehensive analysis of the role of Mll in hematopoiesis in fetal and adult knockout mice has ...

Posted in researches 3 | No Comments »

Unique and Independent Roles for MLL in Adult Hematopoietic Stem Cells and Progenitors.

March 29th, 2008
Unique and Independent Roles for MLL in Adult Hematopoietic Stem Cells and Progenitors. The Mixed Lineage Leukemia (MLL) gene is essential for embryonic hematopoietic stem cell (HSC) development, but its role during adult hematopoiesis is unknown. Using an inducible knockout model, we demonstrate that Mll is ...

Posted in researches 3 | No Comments »