scholarly journals Stem Cell Niches in Glioblastoma: A Neuropathological View

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Davide Schiffer ◽  
Marta Mellai ◽  
Laura Annovazzi ◽  
Valentina Caldera ◽  
Angela Piazzi ◽  
...  
Keyword(s):  
Stem Cells ◽  
Endothelial Cells ◽  
Stem Cell ◽  
Tumor Cells ◽  
Therapeutic Target ◽  
Molecular Mechanisms ◽  
Mechanisms Of Resistance ◽  
Differentiated Cells ◽  
Thin Ring ◽  
Stem Cell Niches

Glioblastoma (GBM) stem cells (GSCs), responsible for tumor growth, recurrence, and resistance to therapies, are considered the real therapeutic target, if they had no molecular mechanisms of resistance, in comparison with the mass of more differentiated cells which are insensitive to therapies just because of being differentiated and nonproliferating. GSCs occur in tumor niches where both stemness status and angiogenesis are conditioned by the microenvironment. In both perivascular and perinecrotic niches, hypoxia plays a fundamental role. Fifteen glioblastomas have been studied by immunohistochemistry and immunofluorescence for stemness and differentiation antigens. It has been found that circumscribed necroses develop inside hyperproliferating areas that are characterized by high expression of stemness antigens. Necrosis developed inside them because of the imbalance between the proliferation of tumor cells and endothelial cells; it reduces the number of GSCs to a thin ring around the former hyperproliferating area. The perinecrotic GSCs are nothing else that the survivors remnants of those populating hyperproliferating areas. In the tumor, GSCs coincide with malignant areas so that the need to detect where they are located is not so urgent.

Designing and Engineering Stem Cell Niches

MRS Bulletin ◽  
2010 ◽  
Vol 35 (8) ◽  
pp. 591-596 ◽  
Author(s):  
Ana I. Teixeira ◽  
Ola Hermanson ◽  
Carsten Werner
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Biology ◽  
Chemical Engineering ◽  
Polyglycolic Acid ◽  
Differentiated Cells ◽  
Extracellular Matrix Components ◽  
Stem Cell Niches

AbstractStem cells have received a lot of attention due to great promises in medical treatment, for example, by replacing lost and sick cells and re-constituting cell populations. There are several classes of stem cells, including embryonic, fetal, and adult tissue specific. More recently, the generation of so-called induced pluripotent stem (iPS) cells from differentiated cells has been established. Common criteria for all types of stem cells include their ability to self-renew and to retain their ability to differentiate in response to specific cues. These characteristics, as well as the instructive steering of the cells into differentiation, are largely dependent on the microenvironment surrounding the cells. Such “stem cell friendly” microenvironments, provided by structural and biochemical components, are often referred to as niches. Biomaterials offer attractive solutions to engineer functional stem cell niches and to steer stem cell state and fatein vitroas well asin vivo. Among materials used so far, promising results have been achieved with low-toxicity and biodegradable polymers, such as polyglycolic acid and related materials, as well as other polymers used as structural “scaffolds” for engineering of extracellular matrix components. To improve the efficiency of stem cell control and the design of the biomaterials, interfaces among stem cell research, developmental biology, regenerative medicine, chemical engineering, and materials research are rapidly developing. Here we provide an introduction to stem cell biology and principles of niche engineering and give an overview of recent advancements in stem cell niche engineering from two stem cell systems—blood and brain.

scholarly journals Plasticity of Intestinal Epithelium: Stem Cell Niches and Regulatory Signals

2020 ◽  
Vol 22 (1) ◽  
pp. 357
Author(s):  
Ken Kurokawa ◽  
Yoku Hayakawa ◽  
Kazuhiko Koike
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Inflammatory Cytokines ◽  
Intestinal Epithelium ◽  
Intestinal Stem Cells ◽  
Signal Pathways ◽  
Epithelial Regeneration ◽  
Cell Functions ◽  
Differentiated Cells ◽  
Stem Cell Niches

The discovery of Lgr5+ intestinal stem cells (ISCs) triggered a breakthrough in the field of ISC research. Lgr5+ ISCs maintain the homeostasis of the intestinal epithelium in the steady state, while these cells are susceptible to epithelial damage induced by chemicals, pathogens, or irradiation. During the regeneration process of the intestinal epithelium, more quiescent +4 stem cells and short-lived transit-amplifying (TA) progenitor cells residing above Lgr5+ ISCs undergo dedifferentiation and act as stem-like cells. In addition, several recent reports have shown that a subset of terminally differentiated cells, including Paneth cells, tuft cells, or enteroendocrine cells, may also have some degree of plasticity in specific situations. The function of ISCs is maintained by the neighboring stem cell niches, which strictly regulate the key signal pathways in ISCs. In addition, various inflammatory cytokines play critical roles in intestinal regeneration and stem cell functions following epithelial injury. Here, we summarize the current understanding of ISCs and their niches, review recent findings regarding cellular plasticity and its regulatory mechanism, and discuss how inflammatory cytokines contribute to epithelial regeneration.

scholarly journals Resolving stem and progenitor cells in the adult mouse incisor through gene co-expression analysis

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Kerstin Seidel ◽  
Pauline Marangoni ◽  
Cynthia Tang ◽  
Bahar Houshmand ◽  
Wen Du ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Expression Analysis ◽  
Adult Mouse ◽  
Deep Understanding ◽  
Lineage Tracing ◽  
Differentiated Cells ◽  
Mouse Incisor ◽  
Stem Cell Niches

Investigations into stem cell-fueled renewal of an organ benefit from an inventory of cell type-specific markers and a deep understanding of the cellular diversity within stem cell niches. Using the adult mouse incisor as a model for a continuously renewing organ, we performed an unbiased analysis of gene co-expression relationships to identify modules of co-expressed genes that represent differentiated cells, transit-amplifying cells, and residents of stem cell niches. Through in vivo lineage tracing, we demonstrated the power of this approach by showing that co-expression module members Lrig1 and Igfbp5 define populations of incisor epithelial and mesenchymal stem cells. We further discovered that two adjacent mesenchymal tissues, the periodontium and dental pulp, are maintained by distinct pools of stem cells. These findings reveal novel mechanisms of incisor renewal and illustrate how gene co-expression analysis of intact biological systems can provide insights into the transcriptional basis of cellular identity.

scholarly journals A Mathematical Model of Average Dynamics in a Stem Cell Hierarchy Suggests the Combinatorial Targeting of Cancer Stem Cells and Progenitor Cells as a Potential Strategy against Tumor Growth

Cancers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2590
Author(s):  
Rodolfo Molina-Peña ◽  
Juan Carlos Tudon-Martinez ◽  
Osvaldo Aquines-Gutiérrez
Keyword(s):  
Mathematical Model ◽  
Stem Cells ◽  
Stem Cell ◽  
Cancer Stem Cells ◽  
Combination Therapy ◽  
Tumor Growth ◽  
Tumor Cells ◽  
Tumor Relapse ◽  
Differentiated Cells ◽  
P Cells

The cancer stem cell hypothesis states that tumors are maintained by a small subpopulation of stem-like cells, often called cancer stem cells (CSCs) or tumor initiating cells. CSCs can self-renew and give rise to more differentiated cells, which comprise the bulk of the tumor. In addition, CSCs are resistant to conventional therapy, which suggests that they are responsible for tumor relapse. This has led researchers to increase efforts to develop directed therapies against CSCs. However, some experiments in mice have shown that the elimination of CSCs might not ensure tumor eradication. This may be due to different events, such as residual CSCs after treatment, the plasticity of cells within the tumor, the presence of different CSCs having their own hierarchy within the same tumor, and the ability of more differentiated cells to maintain the disease, among others. Trying to decipher this complexity may benefit from dissecting the whole in its parts. Here, we hypothesize that tumor relapse after the selective targeting of CSCs may be due to intermediate progenitor (P) cells that can maintain the tumor volume. In order to support the hypothesis, we implemented a mathematical model derived using pseudo-reactions representing the events of each cell subpopulation within the tumor. We aimed to test if a minimal unidirectional hierarchical model consisting of CSCs, P, and terminally differentiated (D) cells could be adjusted to experimental data for selective CSC targeting. We further evaluated therapies ranging from nonselective to specifically directed and combination therapy. We found that selective killing of the CSC compartment has a delaying effect on the overall exponential tumor growth, but was not able to eliminate the disease. We show that therapy that targets both CSCs and intermediate progenitor (P) cells with a sufficient capacity to proliferate and differentiate could represent a more efficient treatment option for tumor depletion. Testing this hypothesis in vivo may allow us to discriminate within the array of possibilities of tumor relapse, and further open the idea of combination therapy against different subpopulations of tumor cells instead of segregating CSCs and bulk tumor cells.

scholarly journals Synergy of molecularly mobile polyrotaxane surfaces with endothelial cell co-culture for mesenchymal stem cell mineralization

RSC Advances ◽  
2021 ◽  
Vol 11 (30) ◽  
pp. 18685-18692
Author(s):  
Hiroki Masuda ◽  
Yoshinori Arisaka ◽  
Masahiro Hakariya ◽  
Takanori Iwata ◽  
Tetsuya Yoda ◽  
...  
Keyword(s):  
Stem Cells ◽  
Endothelial Cells ◽  
Mesenchymal Stem Cells ◽  
Stem Cell ◽  
Endothelial Cell ◽  
Mesenchymal Stem Cell ◽  
Molecular Mobility ◽  
Culture System

Molecular mobility of polyrotaxane surfaces promoted mineralization in a co-culture system of mesenchymal stem cells and endothelial cells.

scholarly journals Wnt5a Signaling in Normal and Cancer Stem Cells

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Yan Zhou ◽  
Thomas J. Kipps ◽  
Suping Zhang
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cancer Progression ◽  
Molecular Mechanisms ◽  
Migration And Invasion ◽  
Target Cells ◽  
Dependent Manner ◽  
Self Renewal ◽  
Surface Receptors ◽  
Canonical Wnt

Wnt5a is involved in activating several noncanonical Wnt signaling pathways, which can inhibit or activate canonical Wnt/β-catenin signaling pathway in a receptor context-dependent manner. Wnt5a signaling is critical for regulating normal developmental processes, including stem cell self-renewal, proliferation, differentiation, migration, adhesion, and polarity. Moreover, the aberrant activation or inhibition of Wnt5a signaling is emerging as an important event in cancer progression, exerting both oncogenic and tumor suppressive effects. Recent studies show the involvement of Wnt5a signaling in regulating normal and cancer stem cell self-renewal, cancer cell proliferation, migration, and invasion. In this article, we review recent findings regarding the molecular mechanisms and roles of Wnt5a signaling in stem cells in embryogenesis and in the normal or neoplastic breast or ovary, highlighting that Wnt5a may have different effects on target cells depending on the surface receptors expressed by the target cell.

scholarly journals Effect of Placental Extract on Omentum Mesenchymal Stem Cells Differentiation in NMRI Mice

2017 ◽  
Vol 7 (1) ◽  
pp. 176
Author(s):  
Maryam Sadat Nezhadfazel ◽  
Kazem Parivar ◽  
Nasim Hayati Roodbari ◽  
Mitra Heydari Nasrabadi
Keyword(s):  
Cell Cycle ◽  
Stem Cells ◽  
Flow Cytometry ◽  
Endothelial Cells ◽  
Mesenchymal Stem Cells ◽  
Control Group ◽  
Fat Cell ◽  
Nmri Mice ◽  
Differentiated Cells ◽  
Placental Extract

Omentum mesenchymal stem cells (OMSCs) could be induced to differentiate into cell varieties under certain conditions. We studied differentiation of OMSCs induced by using placenta extract in NMRI mice. Mesenchymal stem cells (MSCs) were isolated from omentum and cultured with mice placenta extract. MSCs, were assessed after three passages by flow cytometry for CD90, CD44, CD73, CD105, CD34 markers and were recognized their ability to differentiate into bone and fat cell lines. Placenta extract dose was determined with IC50 test then OMSCs were cultured in DMEM and 20% placenta extract.The cell cycle was checked. OMSCs were assayed on 21 days after culture and differentiated cells were determined by flow cytometry and again processed for flow cytometry. CD90, CD44, CD73, CD105 markers were not expressed, only CD34 was their marker. OMSCs were morphologically observed. Differentiated cells are similar to the endothelial cells. Therefore, to identify differentiated cells, CD31 and FLK1 expression were measured. This was confirmed by its expression. G1 phase of the cell cycle shows that OMSCs compared to the control group, were in the differentiation phase. The reason for the differentiation of MSCs into endothelial cells was the sign of presence of VEGF factor in the medium too high value of as a VEGF secreting source.

scholarly journals Current Strategies for Identification of Glioma Stem Cells: Adequate or Unsatisfactory?

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Paola Brescia ◽  
Cristina Richichi ◽  
Giuliana Pelicci
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cancer Stem Cells ◽  
Large Scale ◽  
Molecular Mechanisms ◽  
Cell Phenotype ◽  
Multiple Tumor ◽  
Early Results ◽  
Tumorigenic Potential ◽  
Tumor Types

Cancer stem cells (CSCs) were isolated in multiple tumor types, including human glioblastomas, and although the presence of surface markers selectively expressed on CSCs can be used to isolate them, no marker/pattern of markers are sufficiently robust to definitively identify stem cells in tumors. Several markers were evaluated for their prognostic value with promising early results, however none of them was proven to be clinically useful in large-scale studies, leading to outstanding efforts to identify new markers. Given the heterogeneity of human glioblastomas further investigations are necessary to identify both cancer stem cell-specific markers and the molecular mechanisms sustaining the tumorigenic potential of these cells to develop tailored treatments. Markers for glioblastoma stem cells such as CD133, CD15, integrin-α6, L1CAM might be informative to identify these cells but cannot be conclusively linked to a stem cell phenotype. Overlap of expression, functional state and morphology of different subpopulations lead to carefully consider the techniques employed so far to isolate these cells. Due to a dearth of methods and markers reliably identifying the candidate cancer stem cells, the isolation/enrichment of cancer stem cells to be therapeutically targeted remains a major challenge.

Meristems, Stem Cells, and Stem Cell Niches in Vascular Land Plants

2019 ◽  
pp. 107-133
Author(s):  
Elena Salvi ◽  
Raffaele Dello Ioio ◽  
Laila Moubayidin
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Land Plants ◽  
Stem Cell Niches
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