151
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Artells R, Navarro A, Diaz T, Monzó M. Ultrastructural and immunohistochemical analysis of intestinal myofibroblasts during the early organogenesis of the human small intestine. Anat Rec (Hoboken) 2011; 294:462-71. [PMID: 21284092 DOI: 10.1002/ar.21333] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 11/16/2010] [Indexed: 01/21/2023]
Abstract
Intestinal myofibroblasts (IMFs), also known as pericryptal fibroblasts, are found at the basement membrane of the intestinal epithelium. They are characterized by well-developed endoplasmic reticulum, cytoplasmic fibers, and fibrous extensions called fibronexi. IMFs have structural features in common both with fibroblasts and smooth cells. Vimentin, desmin, and α-smooth-muscle actin (α-SM) are markers commonly used to discriminate between IMFs and smooth muscle cells. Immunohistochemical studies have shown that, when α-SM and vimentin are positive in both IMFs and smooth muscle cells, desmin is negative in IMFs but positive in smooth muscle cells. In the adult intestine, IMFs play an important role in various functions, especially in tissue repair and scar formation during wound healing. In the embryonic intestine, however, wound healing does not occur, and to date, no studies have investigated the first appearance and subsequent evolution of IMFs. In this study, we have examined the human small intestine in embryos at 7, 9, and 11 weeks of development by ultrastructural and immunohistochemical analysis to shed light on the formation of IMFs during these early phases of organogenesis. At 7 weeks, the embryonic mesenchymal cells are similar to proto-myofibroblasts and may be the precursors of the IMFs detected at 9 weeks and more abundantly at 11 weeks by immunohistochemistry. These IMFs seem to mediate information flow between the epithelium and the mesenchyme and thus contribute to the development of the small intestine.
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Affiliation(s)
- Rosa Artells
- Human Anatomy Unit, Molecular Oncology and Embryology Laboratory, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain
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152
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Snippert HJ, Clevers H. Tracking adult stem cells. EMBO Rep 2011; 12:113-22. [PMID: 21252944 DOI: 10.1038/embor.2010.216] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 12/20/2010] [Indexed: 12/17/2022] Open
Abstract
The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context, rather than outside their natural environment. The mouse is an attractive model in which to study adult mammalian stem cells, as numerous experimental systems and genetic tools are available. In this review, we describe strategies commonly used to identify and functionally characterize adult stem cells in mice and discuss their potential, limitations and interpretations, as well as how they have informed our understanding of adult stem-cell biology. An accurate interpretation of physiologically relevant stem-cell assays is crucial to identify adult stem cells and elucidate how they self-renew and give rise to differentiated progeny.
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Affiliation(s)
- Hugo J Snippert
- Hubrecht Institute, KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
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153
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Sanders MA, Majumdar APN. Colon cancer stem cells: implications in carcinogenesis. Front Biosci (Landmark Ed) 2011; 16:1651-62. [PMID: 21196254 DOI: 10.2741/3811] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The cancer stem cell model was described for hematologic malignancies in 1997 and since then evidence has emerged to support it for many solid tumors as well, including colon cancer. This model proposes that certain cells within the tumor mass are pluripotent and capable of self-renewal and have an enhanced ability to initiate distant metastasis. The cancer stem cell model has important implications for cancer treatment, since most current therapies target actively proliferating cells and may not be effective against the cancer stem cells that are responsible for recurrence. In recent years great progress has been made in identifying markers of both normal and malignant colon stem cells. Proteins proposed as colon cancer stem cell markers include CD133, CD44, CD166, ALDH1A1, Lgr5, and several others. In this review we consider the evidence for these proteins as colon cancer stem cell markers and as prognostic indicators of colon cancer survival. Additionally, we discuss potential functions of these proteins and the implications this may have for development of therapies that target colon cancer stem cells.
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Affiliation(s)
- Matthew A Sanders
- Karmanos Cancer Institute, Wayne State University, Detroit, MI 48201, USA
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154
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Abstract
Knowledge of stem cell biology in the intestine is increasing exponentially and it is one of the current hot topics 'of the day'. Yet it is only recently that molecules such as Lgr5 and Bmi1 have been shown to reliably mark stem cells and have revealed the stem cell location throughout the murine gastrointestinal tract. However, there is a scarcity of meaningful work within their human counterpart. Nevertheless, recent studies have demonstrated the processes of niche succession, where one stem cell takes over the entire population of stem cells within a crypt; and monoclonal conversion, whereby the entire crypt becomes a clonal population of cells, are present in the human crypt. This work has also shown how crypts themselves divide and expand in the human colon.
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Affiliation(s)
- Adam Humphries
- Histopathology Unit, London Research Institute, Cancer Research UK, London, UK
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155
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Iwata M, Yokota A. Retinoic acid production by intestinal dendritic cells. VITAMINS AND HORMONES 2011; 86:127-52. [PMID: 21419270 DOI: 10.1016/b978-0-12-386960-9.00006-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Subpopulations of dendritic cells (DCs) in the small intestine and its related lymphoid organs can produce retinoic acid (RA) from vitamin A (retinol). Through the RA production, these DCs play a pivotal role in imprinting lymphocytes with gut-homing specificity, and contribute to the development of immune tolerance by enhancing the differentiation of Foxp3(+) regulatory T cells and inhibiting that of inflammatory Th17 cells. The RA-producing capacity in these DCs mostly depends on the expression of retinal dehydrogenase 2 (RALDH2, ALDH1A2). It is likely that the RALDH2 expression is induced in DCs by the microenvironmental factors in the small intestine and its related lymphoid organs. The major factor responsible for the RALDH2 expression appears to be GM-CSF. RA itself is essential for the GM-CSF-induced RALDH2 expression. IL-4 and IL-13 also enhance RALDH2 expression, but are dispensable. Toll-like receptor-mediated signals can also enhance the GM-CSF-induced RALDH2 expression in immature DCs.
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Affiliation(s)
- Makoto Iwata
- Faculty of Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, Sanuki-shi, Kagawa, Japan
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156
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Quante M, Marrache F, Goldenring JR, Wang TC. TFF2 mRNA transcript expression marks a gland progenitor cell of the gastric oxyntic mucosa. Gastroenterology 2010; 139:2018-2027.e2. [PMID: 20708616 PMCID: PMC2997174 DOI: 10.1053/j.gastro.2010.08.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 07/23/2010] [Accepted: 08/04/2010] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Gastric stem cells are located in the isthmus of the gastric glands and give rise to epithelial progenitors that undergo bipolar migration and differentiation into pit and oxyntic lineages. Although gastric mucus neck cells located below the isthmus express trefoil factor family 2 (TFF2) protein, TFF2 messenger RNA transcripts are concentrated in cells above the neck region in normal corpus mucosa, suggesting that TFF2 transcription is a marker of gastric progenitor cells. METHODS Using a BAC strategy, we generated a transgenic mouse with a tamoxifen-inducible Cre under the control of the TFF2 promoter (TFF2-BAC-Cre(ERT2)) and analyzed the lineage derivation from TFF2 mRNA transcript-expressing (TTE) cells. RESULTS TTE cells were localized to the isthmus, above and distinct from TFF2 protein-expressing mucus neck cells. Lineage tracing revealed that these cells migrated toward the bottom of the gland within 20 days, giving rise to parietal, mucous neck, and chief cells, but not to enterochromaffin-like-cell. Surface mucus cells were not derived from TTE cells and the progeny of the TTE lineage did not survive beyond 200 days. TTE cells were localized in the isthmus adjacent to doublecortin CaM kinase-like-1(+) putative progenitor cells. Induction of spasmolytic polypeptide-expressing metaplasia with DMP-777-induced acute parietal cell loss revealed that this metaplastic phenotype might arise in part through transdifferentiation of chief cells as opposed to expansion of mucus neck or progenitor cells. CONCLUSIONS TFF2 transcript-expressing cells are progenitors for mucus neck, parietal and zymogenic, but not for pit or enterochromaffin-like cell lineages in the oxyntic gastric mucosa.
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Affiliation(s)
- Michael Quante
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, NY
| | - Frederic Marrache
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, NY
| | - James R. Goldenring
- Nashville VA Medical Center and the Departments of Surgery and Cell and Developmental Biology, Epithelial Biology Center and Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN
| | - Timothy C. Wang
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, NY
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157
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Wang Z, Matsudaira P, Gong Z. STORM: a general model to determine the number and adaptive changes of epithelial stem cells in teleost, murine and human intestinal tracts. PLoS One 2010; 5:e14063. [PMID: 21124758 PMCID: PMC2993223 DOI: 10.1371/journal.pone.0014063] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Accepted: 10/29/2010] [Indexed: 01/27/2023] Open
Abstract
Intestinal stem cells play a pivotal role in the epithelial tissue renewal, homeostasis and cancer development. The lack of a general marker for intestinal stem cells across species has hampered analysis of stem cell number in different species and their adaptive changes upon intestinal lesions or during development of cancer. Here a two-dimensional model, named STORM, has been developed to address this issue. By optimizing epithelium renewal dynamics, the model examines the epithelial stem cell number by taking experimental input information regarding epithelium proliferation and differentiation. As the results suggest, there are 2.0-4.1 epithelial stem cells on each pocket section of zebrafish intestine, 2.0-4.1 stem cells on each crypt section of murine small intestine and 1.8-3.5 stem cells on each crypt section of human duodenum. The model is able to provide quick results for stem cell number and its adaptive changes, which is not easy to measure through experiments. Its general applicability to different species makes it a valuable tool for analysis of intestinal stem cells under various pathological conditions.
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Affiliation(s)
- Zhengyuan Wang
- Computation and Systems Biology, Singapore-MIT Alliance, Singapore, Singapore.
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158
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Chia LA, Kuo CJ. The intestinal stem cell. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010. [PMID: 21075344 DOI: 10.1016/b978‐0‐12‐381280‐3.00007‐5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The intestinal epithelium is one of the most rapidly proliferating organs in the body. A complete turnover of the epithelium occurs every 3-5 days in the mouse, a process that is maintained by a small population of intestinal stem cells (ISCs) that reside in the crypt bases. The signals that regulate the behavior of these ISCs are still unknown. This has been due, until recently, to the singular lack of definitive ISC markers. The recent identification of genes that mark functional stem cells has yielded insights into how ISCs are regulated and maintained by their surrounding niche. Herein, we examine the body of literature regarding the precise identity and location of the ISCs, the role of the surrounding niche in ISC maintenance and regulation, as well as the hypothesis that the ISCs are the cells of origin in colorectal cancer.
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Affiliation(s)
- Luis A Chia
- Cancer Biology Program, Stanford University School of Medicine, Stanford, California, USA
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159
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Pruitt SC, Freeland A, Kudla A. Cell cycle heterogeneity in the small intestinal crypt and maintenance of genome integrity. Stem Cells 2010; 28:1250-9. [PMID: 20503265 DOI: 10.1002/stem.450] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Stem cell quiescence has been hypothesized to suppress the rate at which genetic mutations accumulate within tissues by reducing the number of divisions a cell undergoes. However, recent studies have suggested that stem cells in the small intestine are rapidly dividing. This observation raises the issue of whether replication related errors are an important contributor to the accumulation of genetic damage and, if so, how genomic integrity is maintained within the small intestine. Here, reporter-marked small intestinal epithelial cells, resulting from mini-chromosome maintenance protein 2 (Mcm2) gene driven Cre-mediated recombination, are shown to be retained at the +1 position within the crypt and to contribute to the intestinal epithelia over long periods. Additionally, we show that the rate of cycling of +1 position Mcm2-expressing stem cells is heterogeneous with cycling times ranging between 1 and 4 days. Further, this heterogeneity depends on the p53 signaling pathway and could provide the basis for retention and expansion, through niche succession and crypt fission, of genetically intact stem cells. This somatic selection process would require active cellular replication.
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Affiliation(s)
- Steven C Pruitt
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, New York, USA.
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160
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Shaw RL, Kohlmaier A, Polesello C, Veelken C, Edgar BA, Tapon N. The Hippo pathway regulates intestinal stem cell proliferation during Drosophila adult midgut regeneration. Development 2010; 137:4147-58. [PMID: 21068063 DOI: 10.1242/dev.052506] [Citation(s) in RCA: 244] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Intestinal stem cells (ISCs) in the adult Drosophila midgut proliferate to self-renew and to produce differentiating daughter cells that replace those lost as part of normal gut function. Intestinal stress induces the activation of Upd/Jak/Stat signalling, which promotes intestinal regeneration by inducing rapid stem cell proliferation. We have investigated the role of the Hippo (Hpo) pathway in the Drosophila intestine (midgut). Hpo pathway inactivation in either the ISCs or the differentiated enterocytes induces a phenotype similar to that observed under stress situations, including increased stem cell proliferation and expression of Jak/Stat pathway ligands. Hpo pathway targets are induced by stresses such as bacterial infection, suggesting that the Hpo pathway functions as a sensor of cellular stress in the differentiated cells of the midgut. In addition, Yki, the pro-growth transcription factor target of the Hpo pathway, is required in ISCs to drive the proliferative response to stress. Our results suggest that the Hpo pathway is a mediator of the regenerative response in the Drosophila midgut.
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Affiliation(s)
- Rachael L Shaw
- Apoptosis and Proliferation Control Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London, WC2A 3LY, UK
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161
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Pleniceanu O, Harari-Steinberg O, Dekel B. Concise review: Kidney stem/progenitor cells: differentiate, sort out, or reprogram? Stem Cells 2010; 28:1649-60. [PMID: 20652959 PMCID: PMC2996087 DOI: 10.1002/stem.486] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
End-stage renal disease (ESRD) is defined as the inability of the kidneys to remove waste products and excess fluid from the blood. ESRD progresses from earlier stages of chronic kidney disease (CKD) and occurs when the glomerular filtration rate (GFR) is below 15 ml/minute/1.73 m2. CKD and ESRD are dramatically rising due to increasing aging population, population demographics, and the growing rate of diabetes and hypertension. Identification of multipotential stem/progenitor populations in mammalian tissues is important for therapeutic applications and for understanding developmental processes and tissue homeostasis. Progenitor populations are ideal targets for gene therapy, cell transplantation, and tissue engineering. The demand for kidney progenitors is increasing due to severe shortage of donor organs. Because dialysis and transplantation are currently the only successful therapies for ESRD, cell therapy offers an alternative approach for kidney diseases. However, this approach may be relevant only in earlier stages of CKD, when kidney function and histology are still preserved, allowing for the integration of cells and/or for their paracrine effects, but not when small and fibrotic end-stage kidneys develop. Although blood- and bone marrow-derived stem cells hold a therapeutic promise, they are devoid of nephrogenic potential, emphasizing the need to seek kidney stem cells beyond known extrarenal sources. Moreover, controversies regarding the existence of a true adult kidney stem cell highlight the importance of studying cell-based therapies using pluripotent cells, progenitor cells from fetal kidney, or dedifferentiated/reprogrammed adult kidney cells. Stem Cells 2010; 28:1649–1660.
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Affiliation(s)
- Oren Pleniceanu
- Pediatric Stem Cell Research Institute, Sheba Medical Center, Tel Hashomer, Israel
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162
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Zhu X, Zhou X, Lewis MT, Xia L, Wong S. Cancer stem cell, niche and EGFR decide tumor development and treatment response: A bio-computational simulation study. J Theor Biol 2010; 269:138-49. [PMID: 20969880 DOI: 10.1016/j.jtbi.2010.10.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 10/11/2010] [Accepted: 10/11/2010] [Indexed: 12/11/2022]
Abstract
Recent research in cancer biology has suggested the hypothesis that tumors are initiated and driven by a small group of cancer stem cells (CSCs). Furthermore, cancer stem cell niches have been found to be essential in determining fates of CSCs, and several signaling pathways have been proven to play a crucial role in cellular behavior, which could be two important factors in cancer development. To better understand the progression, heterogeneity and treatment response of breast cancer, especially in the context of CSCs, we propose a mathematical model based on the cell compartment method. In this model, three compartments of cellular subpopulations are constructed: CSCs, progenitor cells (PCs), and terminal differentiated cells (TCs). Moreover, (1) the cancer stem cell niche is, considered by modeling its effect on division patterns (symmetric or asymmetric) of CSCs, and (2) the EGFR signaling pathway is integrated by modeling its role in cell proliferation, apoptosis. Our simulation results indicate that (1) a higher probability for symmetric division of CSC may result in a faster expansion of tumor population, and for a larger number of niches, the tumor grows at a slower rate, but the final tumor volume is larger; (2) higher EGFR expression correlates to tumors with larger volumes while a saturation function is observed, and (3) treatments that inhibit tyrosine kinase activity of EGFR may not only repress the tumor volume, but also decrease the CSCs percentages by shifting CSCs from symmetric divisions to asymmetric divisions. These findings suggest that therapies should be designed to effectively control or eliminate the symmetric division of CSCs and to reduce or destroy the CSC niches.
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Affiliation(s)
- Xiuwei Zhu
- Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China
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163
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Karpowicz P, Perrimon N. All for one, and one for all: the clonality of the intestinal stem cell niche. F1000 BIOLOGY REPORTS 2010; 2:73. [PMID: 21173846 PMCID: PMC2989629 DOI: 10.3410/b2-73] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Intestinal epithelia are maintained by intestinal stem cells (ISCs) that divide to replace dying absorptive and secretory cells that make up this tissue. Lineage labeling studies, both in vertebrates and Drosophila, have revealed the relationships between ISCs and their progeny. In addition, a number of signaling pathways involved in ISC proliferation and differentiation have been identified. Further studies will clarify the signals originating from the ISC niche and determine the processes that control the number and uniform distribution of niches throughout the epithelium.
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Affiliation(s)
- Phillip Karpowicz
- Department of Genetics, Harvard Medical School77 Avenue Louis Pasteur, Boston, MA 02115USA
| | - Norbert Perrimon
- Department of Genetics, Harvard Medical School77 Avenue Louis Pasteur, Boston, MA 02115USA
- Howard Hughes Medical Institute4000 Jones Bridge Road, Chevy Chase, MD 20815-6789USA
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164
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Abstract
Self-renewal in the intestinal epithelia is fueled by a population of undifferentiated intestinal stem cells (ISCs) that give rise to daughter or progenitor cells, which can subsequently differentiate into the mature cell types required for normal gut function. The cellular signals that regulate self-renewal are poorly understood and the factors that mediate the transition from a stem cell to a progenitor cell in the gut are unknown. Recent studies have suggested that ISCs are located either at the crypt base interspersed between the Paneth cells (eg, Lgr-5+ve cells) or at or near position 4 within the intestinal crypt (eg, DCAMKL-1 or Bmi-1+ve cells). This raises the possibility that distinct stem cell regions exist in the crypts and that ISC's state of activation will determine how the self-renewal is regulated in the intestinal tract.
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Affiliation(s)
- Shahid Umar
- Department of Internal Medicine, Division of Digestive Diseases, University of Oklahoma Health Sciences Center, 975 NE 10th Street, SL Young BRC West 1268B, Oklahoma City, OK 73104, USA.
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165
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Lee G, Goretsky T, Managlia E, Dirisina R, Singh AP, Brown JB, May R, Yang GY, Ragheb JW, Evers BM, Weber CR, Turner JR, He XC, Katzman RB, Li L, Barrett TA. Phosphoinositide 3-kinase signaling mediates beta-catenin activation in intestinal epithelial stem and progenitor cells in colitis. Gastroenterology 2010; 139:869-81, 881.e1-9. [PMID: 20580720 PMCID: PMC2930080 DOI: 10.1053/j.gastro.2010.05.037] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 05/11/2010] [Accepted: 05/19/2010] [Indexed: 12/21/2022]
Abstract
BACKGROUND & AIMS Mechanisms responsible for crypt architectural distortion in chronic ulcerative colitis (CUC) are not well understood. Data indicate that serine/threonine protein kinase Akt (Akt) signaling cooperates with Wingless (Wnt) to activate beta-catenin in intestinal stem and progenitor cells through phosphorylation at Ser552 (P-beta-catenin(552)). We investigated whether phosphoinositide 3-kinase (PI3K) is required for Akt-mediated activation of beta-catenin during intestinal inflammation. METHODS The class IA subunit of PI3K was conditionally deleted from intestinal epithelial cells in mice named I-pik3r1KO. Acute inflammation was induced in mice and intestines were analyzed by biochemical and histologic methods. The effects of chemically blocking PI3K in colitic interleukin-10(-/-) mice were examined. Biopsy samples from patients were examined. RESULTS Compared with wild-type, I-pik3r1KO mice had reduced T-cell-mediated Akt and beta-catenin signaling in intestinal stem and progenitor cells and limited crypt epithelial proliferation. Biochemical analyses indicated that PI3K-Akt signaling increased nuclear total beta-catenin and P-beta-catenin(552) levels and reduced N-terminal beta-catenin phosphorylation, which is associated with degradation. PI3K inhibition in interleukin-10(-/-) mice impaired colitis-induced epithelial Akt and beta-catenin activation, reduced progenitor cell expansion, and prevented dysplasia. Human samples had increased numbers of progenitor cells with P-beta-catenin(552) throughout expanded crypts and increased messenger RNA expression of beta-catenin target genes in CUC, colitis-associated cancer, tubular adenomas, and sporadic colorectal cancer, compared with control samples. CONCLUSIONS PI3K-Akt signaling cooperates with Wnt to increase beta-catenin signaling during inflammation. PI3K-induced and Akt-mediated beta-catenin signaling are required for progenitor cell activation during the progression from CUC to CAC; these factors might be used as biomarkers of dysplastic transformation in the colon.
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Affiliation(s)
- Goo Lee
- Department of Internal Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Tatiana Goretsky
- Department of Internal Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Elizabeth Managlia
- Department of Internal Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Ramanarao Dirisina
- Department of Internal Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Ajay Pal Singh
- Department of Internal Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Jeffrey B Brown
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Randal May
- Department of Medicine, University of Oklahoma Health Science Center, Oklahoma City, Oklahoma, 73104
| | - Guang-Yu Yang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Josette William Ragheb
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - B Mark Evers
- Department of Surgery and Lucille P Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA
| | - Christopher R. Weber
- Department of Pathology, University of Chicago Pritzker School of Medicine, Chicago, Illinois, USA
| | - Jerrold R Turner
- Department of Pathology, University of Chicago Pritzker School of Medicine, Chicago, Illinois, USA
| | - Xi C He
- Stowers Institute for Medical Research, Kansas City, Missouri 64110
| | - Rebecca B. Katzman
- Department of Internal Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Linheng Li
- Stowers Institute for Medical Research, Kansas City, Missouri 64110,Department of Pathology and Laboratory Medicine, Kansas University Medical Center, Kansas City, Kansas 66160
| | - Terrence A Barrett
- Department of Internal Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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166
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Braga Neto MB, Aguiar CV, Maciel JG, Oliveira BMC, Sevilleja JE, Oriá RB, Brito GAC, Warren CA, Guerrant RL, Lima AAM. Evaluation of HIV protease and nucleoside reverse transcriptase inhibitors on proliferation, necrosis, apoptosis in intestinal epithelial cells and electrolyte and water transport and epithelial barrier function in mice. BMC Gastroenterol 2010; 10:90. [PMID: 20701796 PMCID: PMC2931456 DOI: 10.1186/1471-230x-10-90] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 08/11/2010] [Indexed: 12/29/2022] Open
Abstract
Background Protease inhibitors (PI's) and reverse transcriptase drugs are important components of highly active antiretroviral therapy (HAART) for treating human acquired immunodeficiency syndrome (AIDS). Long-term clinical therapeutic efficacy and treatment compliance of these agents have been limited by undesirable side-effects, such as diarrhea. This study aims to investigate the effects of selected antiretroviral agents on intestinal histopathology and function in vivo and on cell proliferation and death in vitro. Methods Selected antiretroviral drugs were given orally over 7 days, to Swiss mice, as follows: 100 mg/kg of nelfinavir (NFV), indinavir (IDV), didanosine (DDI) or 50 mg/kg of zidovudine (AZT). Intestinal permeability measured by lactulose and mannitol assays; net water and electrolyte transport, in perfused intestinal segments; and small intestinal morphology and cell apoptosis were assessed in treated and control mice. In vitro cell proliferation was evaluated using the WST-1 reagent and apoptosis and necrosis by flow cytometry analysis. Results NFV, IDV, AZT and DDI caused significant reductions in duodenal and in jejunal villus length (p < 0.05). IDV and AZT increased crypt depth in the duodenum and AZT increased crypt depth in the jejunum. NFV, AZT and DDI significantly decreased ileal crypt depth. All selected antiretroviral drugs significantly increased net water secretion and electrolyte secretion, except for DDI, which did not alter water or chloride secretion. Additionally, only NFV significantly increased mannitol and lactulose absorption. NFV and IDV caused a significant reduction in cell proliferation in vitro at both 24 h and 48 h. DDI and AZT did not alter cell proliferation. There was a significant increase in apoptosis rates in IEC-6 cells after 24 h with 70 ug/mL of NFV (control: 4.7% vs NFV: 22%) while IDV, AZT and DDI did not show any significant changes in apoptosis compared to the control group. In jejunal sections, IDV and NFV significantly increased the number of TUNEL positive cells. Conclusion The PI's, NFV and IDV, increased cell apoptosis in vivo, water and electrolyte secretion and intestinal permeability and decreased villus length and cell proliferation. NFV was the only drug tested that increased cell apoptosis in vitro. The nucleoside reverse transcriptase inhibitors, AZT and DDI, did not affect cell apoptosis or proliferation. These findings may partly explain the intestinal side-effects associated with PI's.
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Affiliation(s)
- Manuel B Braga Neto
- Institute of Biomedicine and Clinical Research Unit-University Hospital, Federal University of Ceará, Fortaleza, Brazil
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167
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Abstract
Self-renewal in the intestinal epithelia is fueled by a population of undifferentiated intestinal stem cells (ISCs) that give rise to daughter or progenitor cells, which can subsequently differentiate into the mature cell types required for normal gut function. The cellular signals that regulate self-renewal are poorly understood and the factors that mediate the transition from a stem cell to a progenitor cell in the gut are unknown. Recent studies have suggested that ISCs are located either at the crypt base interspersed between the Paneth cells (eg, Lgr-5+ve cells) or at or near position 4 within the intestinal crypt (eg, DCAMKL-1 or Bmi-1+ve cells). This raises the possibility that distinct stem cell regions exist in the crypts and that ISC's state of activation will determine how the self-renewal is regulated in the intestinal tract.
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168
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Abstract
This unit describes the theory and detailed protocols for performing in vivo lineage tracing from Lgr5(+ve) intestinal stem cells using an Lgr5-EGFP-ires-CreERT2/Rosa26lacZ mouse model. Lineage tracing can be initiated in mice at any age by administering limiting doses of the hormone tamoxifen. This activates the lacZ reporter gene in the Lgr5(+ve) stem cells, which subsequently transmit this permanent genetic mark to their progeny as they repopulate the epithelium during normal homeostasis. Because the Lgr5(+ve) cells are long-lived, self-renewing stem cells, they continuously generate lacZ progeny, which contribute to tissue renewal over the entire lifetime of the mouse. The same protocols can be applied to performing in vivo lineage tracing from other Lgr5(+ve) stem cell populations, including those in the hair-follicle and stomach.
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Affiliation(s)
- Nick Barker
- Hubrecht Institute for Developmental Biology and Stem Cell Research, and University Medical Center Utrecht (UMCU), Utrecht, The Netherlands
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169
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Cervelló I, Gil-Sanchis C, Mas A, Delgado-Rosas F, Martínez-Conejero JA, Galán A, Martínez-Romero A, Martínez S, Navarro I, Ferro J, Horcajadas JA, Esteban FJ, O'Connor JE, Pellicer A, Simón C. Human endometrial side population cells exhibit genotypic, phenotypic and functional features of somatic stem cells. PLoS One 2010; 5:e10964. [PMID: 20585575 PMCID: PMC2891991 DOI: 10.1371/journal.pone.0010964] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 05/08/2010] [Indexed: 01/10/2023] Open
Abstract
During reproductive life, the human endometrium undergoes around 480 cycles of growth, breakdown and regeneration should pregnancy not be achieved. This outstanding regenerative capacity is the basis for women's cycling and its dysfunction may be involved in the etiology of pathological disorders. Therefore, the human endometrial tissue must rely on a remarkable endometrial somatic stem cells (SSC) population. Here we explore the hypothesis that human endometrial side population (SP) cells correspond to somatic stem cells. We isolated, identified and characterized the SP corresponding to the stromal and epithelial compartments using endometrial SP genes signature, immunophenotyping and characteristic telomerase pattern. We analyzed the clonogenic activity of SP cells under hypoxic conditions and the differentiation capacity in vitro to adipogenic and osteogenic lineages. Finally, we demonstrated the functional capability of endometrial SP to develop human endometrium after subcutaneous injection in NOD-SCID mice. Briefly, SP cells of human endometrium from epithelial and stromal compartments display genotypic, phenotypic and functional features of SSC.
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Affiliation(s)
- Irene Cervelló
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
- Valencia Stem Cell Bank, CIPF, Valencia, Spain
| | - Claudia Gil-Sanchis
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
- Valencia Stem Cell Bank, CIPF, Valencia, Spain
| | - Aymara Mas
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
- Valencia Stem Cell Bank, CIPF, Valencia, Spain
| | | | | | | | | | - Sebastian Martínez
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
| | - Ismael Navarro
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
| | - Jaime Ferro
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
| | - José Antonio Horcajadas
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
- iGenomix, Valencia, Spain
| | - Francisco José Esteban
- Department of Experimental Biology, Systems Biology Unit, University of Jaén, Jaén, Spain
| | | | - Antonio Pellicer
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
- Department of Obstetrics and Gynecology, Hospital Universitario “La Fe”, Valencia, Spain
| | - Carlos Simón
- Fundación IVI-Instituto Universitario IVI, Universidad de Valencia, Valencia, Spain
- Valencia Stem Cell Bank, CIPF, Valencia, Spain
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170
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Bjerknes M, Cheng H. Cell Lineage metastability in Gfi1-deficient mouse intestinal epithelium. Dev Biol 2010; 345:49-63. [PMID: 20599897 DOI: 10.1016/j.ydbio.2010.06.021] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2009] [Revised: 06/07/2010] [Accepted: 06/15/2010] [Indexed: 01/28/2023]
Abstract
Elucidating the mechanisms determining multipotent progenitor cell fate remains a fundamental project of contemporary biology. Various tissues of mice and men with defects in the zinc-finger transcriptional repressor Gfi1 have dramatic perturbations in the proportions of their differentiated cell types. In Gfi1-deficient intestinal epithelium there is a shift from mucous and Paneth towards enteroendocrine cells, leading to the proposal that Gfi1 functions in the allocation of the progeny derived from a hypothetical common granulocytic progenitor. However, studies of clones have yielded no evidence of such a common progenitor prompting us to investigate alternate mechanisms explaining the Gfi1-deficient phenotype. We report that mucous and Paneth but not enteroendocrine lineage cells normally express Gfi1. Sporadic mucous and Paneth lineage cells in the crypts of Gfi1-deficient mice aberrantly express the pro-enteroendocrine transcription factor Neurog3, indicating that stable repression of Neurog3 in these lineages requires Gfi1. Importantly, we also find mucous and Paneth lineage cells in various stages of cellular reprogramming into the enteroendocrine lineage in Gfi1-deficient mice. We propose that mucous and Paneth cell lineage metastability, rather than reallocation at the level of a hypothetical common granulocytic progenitor, is responsible for the shifts in cell type proportions observed in Gfi1-deficient intestinal epithelium.
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Affiliation(s)
- Matthew Bjerknes
- Department of Medicine, Clinical Science Division, Medical Sciences Building, Room 6334, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8.
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171
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Intestinal stem cells and their roles during mucosal injury and repair. J Surg Res 2010; 167:1-8. [PMID: 20599211 DOI: 10.1016/j.jss.2010.04.037] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 04/13/2010] [Accepted: 04/20/2010] [Indexed: 01/10/2023]
Abstract
The ability of the host to respond to intestinal injury requires the regeneration of native tissue through a highly orchestrated response from the intestinal stem cells, a population of cells located within the intestinal crypts that have the capability to repopulate the entire villous. The field of intestinal stem cell biology is thus of great interest to surgeons and non-surgeons alike, given its relevance to diseases of intestinal injury and inflammation such as inflammatory bowel disease, trauma, and necrotizing enterocolitis. The field of intestinal stem cell research has been advanced recently by the identification of the putative marker, Lgr5, which has allowed for the isolation and further characterization of the intestinal stem cell. Under the control of the WNT signaling pathway, Lgr5 marks the rapidly dividing cells of the intestinal crypt, and identifies a population of cells that is capable of regenerating the entire villous. We now review the identification of Lgr5 as an intestinal stem cell marker, identify controversies in the intestinal stem cell field, and highlight the response of the intestinal stem cell to injury within the intestinal mucosa that may occur clinically.
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172
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Barker N, Clevers H. Leucine-rich repeat-containing G-protein-coupled receptors as markers of adult stem cells. Gastroenterology 2010; 138:1681-96. [PMID: 20417836 DOI: 10.1053/j.gastro.2010.03.002] [Citation(s) in RCA: 259] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 03/03/2010] [Accepted: 03/05/2010] [Indexed: 12/18/2022]
Abstract
Molecular markers are used to characterize and track adult stem cells. Colon cancer research has led to the identification of 2 related receptors, leucine-rich repeat-containing, G-protein-coupled receptors (Lgr)5 and Lgr6, that are expressed by small populations of cells in a variety of adult organs. Genetic mouse models have allowed the visualization, isolation, and genetic marking of Lgr5(+ve) and Lgr6(+ve) cells and provided evidence that they are stem cells. The Lgr5(+ve) cells were found to occupy locations not commonly associated with stem cells in the stomach, small intestine, colon, and hair follicles. A multipotent population of skin stem cells express Lgr6. Single Lgr5(+ve) stem cells from the small intestine and the stomach can be cultured into long-lived organoids. Further studies of these markers might reveal adult stem cell populations in additional tissues. Identification of the ligands for Lgr5 and 6 will help elucidate stem cell functions and modes of intracellular signaling.
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Affiliation(s)
- Nick Barker
- Hubrecht Institute, Uppsalalaan, Utrecht, The Netherlands.
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173
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Giandomenico V. Molecular pathology of gastrointestinal neuroendocrine tumours – selected topics. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.mpdhp.2010.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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174
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Faro A, Boj SF, Clevers H. Fishing for intestinal cancer models: unraveling gastrointestinal homeostasis and tumorigenesis in zebrafish. Zebrafish 2010; 6:361-76. [PMID: 19929219 DOI: 10.1089/zeb.2009.0617] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Zebrafish has proven to be a highly versatile model for comprehensive studies of gene function in development. Given that the molecular pathways involved in epithelial carcinogenesis appear to be conserved across vertebrates, zebrafish is now considered as a valid model to study tumor biology. Development and homeostasis in multicellular organisms are dependent on a complex interplay between cell proliferation, migration, differentiation, and cell death. The Wnt signaling pathway is a major signaling pathway during embryonic development and is the key regulator of self-renewal homeostasis in several adult tissues. A large body of knowledge on adult stem-cell biology has arisen from the study of the intestinal epithelium over the past 20 years. The Wnt pathway has appeared as its principal regulator of homeostatic self-renewal. Moreover, most cancers of the intestine are caused by activating mutations in the Wnt pathway. Recently, zebrafish models have been developed to study Wnt pathway-induced cancer. An appealing avenue for cancer research in zebrafish is large-scale screens to identify chemotherapeutic and chemopreventive agents in conjunction with the in vivo imaging approaches that zebrafish affords.
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Affiliation(s)
- Ana Faro
- Hubrecht Institute for Developmental Biology and Stem Cell Research, Utrecht, The Netherlands
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175
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Gastric carcinogenesis and the cancer stem cell hypothesis. Gastric Cancer 2010; 13:11-24. [PMID: 20373071 DOI: 10.1007/s10120-009-0537-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Accepted: 12/02/2009] [Indexed: 02/07/2023]
Abstract
Normal stem cells (NSCs) are reported to exist in most tissues, including the brain, bone marrow, and probably the gastrointestinal tract. In the latter case, they are thought to possess both the self-renewal capacity and asymmetrical division capacity to generate progenitor cells which differentiate into epithelial cells. NSCs in the normal gastric mucosa are thought to be present in the proliferative zone of the neck/isthmus region, and to undergo a complex bipolar migration from the neck/isthmus region either upward or downward, becoming differentiated normal epithelial cells. NSCs in human gastric mucosa are difficult to identify due to the current lack of a useful marker. A precise definition of cancer stem cells (CSCs) is still under discussion. CSCs are generally defined as malignant cells with NSC capacity. However, many studies of CSCs have demonstrated their rapid growth and high metastatic potential, while NSCs are thought to be slow-growing and self-renewing, and to lack functional capacities such as cell migration and attachment. Recent evidence suggests the existence of CSCs in a wide variety of solid tumors. In this review, we will discuss the existence and cell biology of gastric NSCs and CSCs. We will also discuss whether gastric CSCs originate as organ-specific stem cells or as bone marrow-derived cells (BMDCs). Under certain conditions, the local microenvironment may promote the development of gastric cancer. Thus, Helicobacter pylori infection and the accompanying chronic inflammatory processes will supply critical initiators inducing cell growth and the tissue repair response, leading to carcinogenesis. This mechanism will be discussed in light of stem cell research. Progress in stem cell research in the gastric field is still limited to experimental animal models. However, recent studies should enhance our understanding of human cancer biology, and provide novel tools for the treatment of incurable gastric cancer.
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176
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Affiliation(s)
- Hans Clevers
- Hubrecht Institute for Developmental Biology and Stem Cell Research, Utrecht, The Netherlands.
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177
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May R, Sureban SM, Hoang N, Riehl TE, Lightfoot SA, Ramanujam R, Wyche JH, Anant S, Houchen CW. Doublecortin and CaM kinase-like-1 and leucine-rich-repeat-containing G-protein-coupled receptor mark quiescent and cycling intestinal stem cells, respectively. Stem Cells 2010; 27:2571-9. [PMID: 19676123 DOI: 10.1002/stem.193] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It is thought that small intestinal epithelia (IE) undergo continuous self-renewal primarily due to their population of undifferentiated stem cells. These stem cells give rise to transit amplifying (daughter/progenitor) cells, which can differentiate into all mature cell types required for normal gut function. Identification of stem cells in IE is paramount to fully understanding this renewal process. One major obstacle in gastrointestinal stem cell biology has been the lack of definitive markers that identify small intestinal stem cells (ISCs). Here we demonstrate that the novel putative ISC marker doublecortin and CaM kinase-like-1 (DCAMKL-1) is predominantly expressed in quiescent cells in the lower two-thirds of intestinal crypt epithelium and in occasional crypt-based columnar cells (CBCs). In contrast, the novel putative stem cell marker leucine-rich-repeat-containing G-protein-coupled receptor (LGR5) is observed in rapidly cycling CBCs and in occasional crypt epithelial cells. Furthermore, functionally quiescent DCAMKL-1+ crypt epithelial cells retain bromo-deoxyuridine in a modified label retention assay. Moreover, we demonstrate that DCAMKL-1 is a cell surface expressing protein; DCAMKL-1+ cells, isolated from the adult mouse small intestine by fluorescence activated cell sorting, self-renew and ultimately form spheroids in suspension culture. These spheroids formed glandular epithelial structures in the flanks of athymic nude mice, which expressed multiple markers of gut epithelial lineage. Thus, DCAMKL-1 is a marker of quiescent ISCs and can be distinguished from the cycling stem/progenitors (LGR5+). Moreover, DCAMKL-1 can be used to isolate normal small intestinal stem cells and represents a novel research tool for regenerative medicine and cancer therapy.
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Affiliation(s)
- Randal May
- Department of Medicine,The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
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178
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Yanai S, Adachi Y, Shi M, Shigematsu A, Shima C, Imai Y, Kwon AH, Ikehara S. Adult bone marrow cells can differentiate into hemopoietic cells and endothelial cells but not into other lineage cells in normal growth and normal life. Int J Hematol 2010; 91:213-8. [PMID: 20087796 DOI: 10.1007/s12185-009-0479-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2009] [Revised: 12/05/2009] [Accepted: 12/10/2009] [Indexed: 01/20/2023]
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179
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Kato K, Takao T, Kuboyama A, Tanaka Y, Ohgami T, Yamaguchi S, Adachi S, Yoneda T, Ueoka Y, Kato K, Hayashi S, Asanoma K, Wake N. Endometrial cancer side-population cells show prominent migration and have a potential to differentiate into the mesenchymal cell lineage. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 176:381-92. [PMID: 20008133 PMCID: PMC2797898 DOI: 10.2353/ajpath.2010.090056] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/24/2009] [Indexed: 11/20/2022]
Abstract
Cancer stem-like cell subpopulations, referred to as "side-population" (SP) cells, have been identified in several tumors based on their ability to efflux the fluorescent dye Hoechst 33342. Although SP cells have been identified in the normal human endometrium and endometrial cancer, little is known about their characteristics. In this study, we isolated and characterized the SP cells in human endometrial cancer cells and in rat endometrial cells expressing oncogenic human K-Ras protein. These SP cells showed i) reduction in the expression levels of differentiation markers; ii) long-term proliferative capacity of the cell cultures; iii) self-renewal capacity in vitro; iv) enhancement of migration, lamellipodia, and uropodia formation; and v) enhanced tumorigenicity. In nude mice, SP cells formed large, invasive tumors, which were composed of both tumor cells and stromal-like cells with enriched extracellular matrix. The expression levels of vimentin, alpha-smooth muscle actin, and collagen III were enhanced in SP tumors compared with the levels in non-SP tumors. In addition, analysis of microdissected samples and fluorescence in situ hybridization of Hec1-SP-tumors showed that the stromal-like cells with enriched extracellular matrix contained human DNA, confirming that the stromal-like cells were derived from the inoculated cells. Moreober, in a Matrigel assay, SP cells differentiated into alpha-smooth muscle actin-expressing cells. These findings demonstrate that SP cells have cancer stem-like cell features, including the potential to differentiate into the mesenchymal cell lineage.
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Affiliation(s)
- Kiyoko Kato
- Department of Obstetrics and Gynecology, School of Medicine, Kyushu University, Fukuoka, Japan.
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180
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Chopra DP, Dombkowski AA, Stemmer PM, Parker GC. Intestinal epithelial cells in vitro. Stem Cells Dev 2010; 19:131-42. [PMID: 19580443 PMCID: PMC3136723 DOI: 10.1089/scd.2009.0109] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 07/06/2009] [Indexed: 02/06/2023] Open
Abstract
Recent advances in the biology of stem cells has resulted in significant interest in the development of normal epithelial cell lines from the intestinal mucosa, both to exploit the therapeutic potential of stem cells in tissue regeneration and to develop treatment models of degenerative disorders of the digestive tract. However, the difficulty of propagating cell lines of normal intestinal epithelium has impeded research into the molecular mechanisms underlying differentiation of stem/progenitor cells into the various intestinal lineages. Several short-term organ/organoid and epithelial cell culture models have been described. There is a dearth of long-term epithelial and/or stem cell cultures of intestine. With an expanding role of stem cells in the treatment of degenerative disorders, there is a critical need for additional efforts to develop in vitro models of stem/progenitor epithelial cells of intestine. The objective of this review is to recapitulate the current status of technologies and knowledge for in vitro propagation of intestinal epithelial cells, markers of the intestinal stem cells, and gene and protein expression profiles of the intestinal cellular differentiation.
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Affiliation(s)
- Dharam P. Chopra
- Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan
| | - Alan A. Dombkowski
- Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan
| | - Paul M. Stemmer
- Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan
| | - Graham C. Parker
- Carman and Ann Adams Department of Pediatrics, Wayne State University, Detroit, Michigan
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181
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Richmond CA, Breault DT. Regulation of gene expression in the intestinal epithelium. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 96:207-29. [PMID: 21075346 DOI: 10.1016/b978-0-12-381280-3.00009-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Regulation of gene expression within the intestinal epithelium is complex and controlled by various signaling pathways that regulate the balance between proliferation and differentiation. Proliferation is required both to grow and to replace cells lost through apoptosis and attrition, yet in all but a few cells, differentiation must take place to prevent uncontrolled growth (cancer) and to provide essential functions. In this chapter, we review the major signaling pathways underlying regulation of gene expression within the intestinal epithelium, based primarily on data from mouse models, as well as specific morphogens and transcription factor families that have a major role in regulating intestinal gene expression, including the Hedgehog family, Forkhead Box (FOX) factors, Homeobox (HOX) genes, ParaHox genes, GATA transcription factors, canonical Wnt/β-catenin signaling, EPH/Ephrins, Sox9, BMP signaling, PTEN/PI3K, LKB1, K-RAS, Notch pathway, HNF, and MATH1. We also briefly highlight important emerging areas of gene regulation, including microRNA (miRNA) and epigenetic regulation.
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Affiliation(s)
- Camilla A Richmond
- Division of Gastroenterology, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts, USA
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182
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Potten CS, Gandara R, Mahida YR, Loeffler M, Wright NA. The stem cells of small intestinal crypts: where are they? Cell Prolif 2009; 42:731-50. [PMID: 19788585 PMCID: PMC6496740 DOI: 10.1111/j.1365-2184.2009.00642.x] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Accepted: 05/27/2009] [Indexed: 12/11/2022] Open
Abstract
Recently, there has been resurgence of interest in the question of small intestinal stem cells, their precise location and numbers in the crypts. In this article, we attempt to re-assess the data, including historical information often omitted in recent studies on the subject. The conclusion we draw is that the evidence supports the concept that active murine small intestinal stem cells in steady state are few in number and are proliferative. There are two evolving, but divergent views on their location (which may be more related to scope of capability and reversibility than to location) several lineage labelling and stem cell self-renewing studies (based on Lgr5 expression) suggest a location intercalated between the Paneth cells (crypt base columnar cells (CBCCs)), or classical cell kinetic, label-retention and radiobiological evidence plus other recent studies, pointing to a location four cell positions luminally from the base of the crypt The latter is supported by recent lineage labelling of Bmi-1-expressing cells and by studies on expression of Wip-1 phosphatase. The situation in the human small intestine remains unclear, but recent mtDNA mutation studies suggest that the stem cells in humans are also located above the Paneth cell zone. There could be a distinct and as yet undiscovered relationship between these observed traits, with stem cell properties both in cells of the crypt base and those at cell position 4.
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183
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van der Flier LG, Clevers H. Stem cells, self-renewal, and differentiation in the intestinal epithelium. Annu Rev Physiol 2009; 71:241-60. [PMID: 18808327 DOI: 10.1146/annurev.physiol.010908.163145] [Citation(s) in RCA: 1241] [Impact Index Per Article: 82.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The mammalian intestine is covered by a single layer of epithelial cells that is renewed every 4-5 days. This high cell turnover makes it a very attractive and comprehensive adult organ system for the study of cell proliferation and differentiation. The intestine is composed of proliferative crypts, which contain intestinal stem cells, and villi, which contain differentiated specialized cell types. Through the recent identification of Lgr5, an intestinal stem cell marker, it is now possible to visualize stem cells and study their behavior and differentiation in a much broader context. In this review we describe the identification of intestinal stem cells. We also discuss genetic studies that have helped to elucidate those signals important for progenitor cells to differentiate into one of the specialized intestinal epithelial cell types. These studies describe a genetic hierarchy responsible for cell fate commitment in normal gut physiology. Where relevant we also mention aberrant deregulation of these molecular pathways that results in colon cancer.
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Affiliation(s)
- Laurens G van der Flier
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences & University Medical Center Utrecht, 3584 CT, Utrecht, The Netherlands.
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184
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Abstract
The epithelial cell lining of the gastrointestinal tract is the most rapidly proliferating tissue in the body. The constant state of renewal of differentiated epithelial cells is sustained by a continual supply of progeny from multipotent progenitors that originate from stem cells located within the intestinal crypts. In addition to supporting normal epithelial homeostasis, intestinal stem cells (ISC) are thought to play an important role in the rapid expansion of the gut during development, tissue regeneration following injury or surgical loss, and malignancy. Because of the lack of specific ISC markers required to isolate and characterize these cells, our current knowledge of the biology of ISC results largely from indirect measures of their behavior published during the past 40 years. The recent description of several potential ISC markers and the use of transgenic mice, both as a tool to lineage trace and to isolate specific cells expressing these markers, have provided a tremendous advancement to our current understanding of these cells. This brief review provides a general historical overview of our understanding of ISC and the tools available to study their behavior in the context of normal and pathological conditions, as well as potential future clinical applications that may result from this exciting area of research.
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185
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McDonald SAC, Graham TA, Schier S, Wright NA, Alison MR. Stem cells and solid cancers. Virchows Arch 2009; 455:1-13. [PMID: 19499244 DOI: 10.1007/s00428-009-0783-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 04/22/2009] [Accepted: 04/28/2009] [Indexed: 02/06/2023]
Abstract
Recently, there have been significant advances in our knowledge of stem cells found in tissues that can develop solid tumours. In particular, novel stem cell markers have been identified for the first time identifying multipotential cells: a required characteristic of a stem cell. The scarcity of cancer stem cells has been questioned. Current dogma states that they are rare, but novel research has suggested that this may not be the case. Here, we review the latest literature on stem cells, particularly cancer stem cells within solid tumours. We discuss current thinking on how stem cells develop into cancer stem cells and how they protect themselves from doing so and do they express unique markers that can be used to detect stem cells. We attempt to put into perspective these latest advances in stem cell biology and their potential for cancer therapy.
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Affiliation(s)
- Stuart A C McDonald
- Centre for Gastroenterology, Institute of Cell and Molecular Science, Barts and the London School of Medicine and Dentistry, Blizard Building, 4 Newark Street, Whitechapel, London, E1 2AT, UK.
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186
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p21(waf1/cip1) deficiency does not perturb the intestinal crypt stem cell population after massive small bowel resection. J Pediatr Surg 2009; 44:1065-71; discussion 1071. [PMID: 19524718 PMCID: PMC2697119 DOI: 10.1016/j.jpedsurg.2009.02.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Accepted: 02/17/2009] [Indexed: 01/21/2023]
Abstract
BACKGROUND After small bowel resection (SBR), adaptation is initiated in intestinal crypts where stem cells reside. Prior studies revealed SBR-induced enterocyte proliferation requires the expression of p21(waf1/cip1). As deficient expression of p21(waf1/cip1) has been shown to result in reduced numbers of hematopoietic stem cells. We sought to test the hypothesis that p21(waf1/cip1)deficiency similarly perturbs the intestinal stem cell population after SBR. METHODS Control (n = 21; C57Bl/6) and p21(waf1/cip1)-null mice (n = 30) underwent 50% proximal SBR or sham operation. After 3 days, the ileum was harvested and the crypt stem cell population evaluated by counting crypt base columnar cells on histologic sections, determining the expression of Musashi-1 and Lgr5, and profiling the transcriptional expression of 84 known stem cell genes. RESULTS There were no significant differences in crypt base columnar cells, expression of Musashi-1 or Lgr5, or in stem cell gene expression after SBR in control mice. Furthermore, there were no differences in these markers between controls and p21(waf1/cip1)-null mice. CONCLUSION In contrast with bone marrow stem cells, the stem cell population of the gut is unaffected by deficient expression of p21(waf1/cip1). Additional mechanisms for the role of p21(waf1/cip1) in small bowel proliferation and adaptation after massive SBR must be considered.
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187
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Fellous TG, McDonald SA, Burkert J, Humphries A, Islam S, De-Alwis NM, Gutierrez-Gonzalez L, Tadrous PJ, Elia G, Kocher HM, Bhattacharya S, Mears L, El-Bahrawy M, Turnbull DM, Taylor RW, Greaves LC, Chinnery PF, Day CP, Wright NA, Alison MR. A Methodological Approach to Tracing Cell Lineage in Human Epithelial Tissues. Stem Cells 2009; 27:1410-20. [DOI: 10.1002/stem.67] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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188
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Carlone DL. Functional analysis of adult stem cells using Cre-mediated lineage tracing. CURRENT PROTOCOLS IN STEM CELL BIOLOGY 2009; Chapter 5:Unit 5A.2. [PMID: 19455543 DOI: 10.1002/9780470151808.sc05a02s9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Lineage-tracing has been used for decades to establish cell fate maps during development. Recently, with the advent of genetic lineage-tracing techniques (employing Cre-lox recombination), it has been possible to permanently mark progenitor/stem cell populations within somatic tissues. In addition, pulse-chase studies have shown that only stem cells are capable of producing labeled progeny after an extensive period of chase. This unit focuses on the protocols used to target putative adult stem cells in vivo. Using these techniques, one should be able to functionally confirm or deny the stem cell capacity of a given cell population.
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Affiliation(s)
- Diana L Carlone
- Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts
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189
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Joubert D, Hollande F, Jay P, Legraverend C. Les cellules souches intestinales. Med Sci (Paris) 2009; 25:441-4. [DOI: 10.1051/medsci/2009255441] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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190
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van der Flier LG, van Gijn ME, Hatzis P, Kujala P, Haegebarth A, Stange DE, Begthel H, van den Born M, Guryev V, Oving I, van Es JH, Barker N, Peters PJ, van de Wetering M, Clevers H. Transcription factor achaete scute-like 2 controls intestinal stem cell fate. Cell 2009; 136:903-12. [PMID: 19269367 DOI: 10.1016/j.cell.2009.01.031] [Citation(s) in RCA: 540] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Revised: 11/07/2008] [Accepted: 01/07/2009] [Indexed: 02/07/2023]
Abstract
The small intestinal epithelium is the most rapidly self-renewing tissue of mammals. Proliferative cells are confined to crypts, while differentiated cell types predominantly occupy the villi. We recently demonstrated the existence of a long-lived pool of cycling stem cells defined by Lgr5 expression and intermingled with post-mitotic Paneth cells at crypt bottoms. We have now determined a gene signature for these Lgr5 stem cells. One of the genes within this stem cell signature is the Wnt target Achaete scute-like 2 (Ascl2). Transgenic expression of the Ascl2 transcription factor throughout the intestinal epithelium induces crypt hyperplasia and ectopic crypts on villi. Induced deletion of the Ascl2 gene in adult small intestine leads to disappearance of the Lgr5 stem cells within days. The combined results from these gain- and loss-of-function experiments imply that Ascl2 controls intestinal stem cell fate.
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191
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Brabletz S, Schmalhofer O, Brabletz T. Gastrointestinal stem cells in development and cancer. J Pathol 2009; 217:307-17. [PMID: 19031475 DOI: 10.1002/path.2475] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
An enormous body of knowledge about the biology of stem cells and their role in development, tissue homeostasis and cancer formation has been gained in the last 20 years. This review gives a comprehensive overview on knowledge about localization and regulation of normal gastrointestinal stem cells and links it to our understanding of gastrointestinal tumourigenesis and malignant progression in the light of the cancer stem cell concept. The focus is on intestinal stem cells and newly identified stem cell factors, such as the beta-catenin target gene Lgr5. The basis of intestinal stem cell regulation is a permanent crosstalk between epithelial and underlying mesenchymal cells in the intestinal stem cell niche. This crosstalk is mediated by crucial pathways, including the Wnt, Hedgehog (HH), Notch, PI3K and BMP pathways. Disturbances in this fine-regulated interaction can both initiate intestinal tumours and, in association with additional genetic alterations or environmental activation of embryonic processes such as epithelial-mesenchymal transition (EMT), lead to tumour invasion and metastasis.
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Affiliation(s)
- S Brabletz
- Department of Visceral Surgery and Comprehensive Cancer Centre, University Medical Centre Freiburg, Germany.
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192
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Haegebarth A, Clevers H. Wnt signaling, lgr5, and stem cells in the intestine and skin. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 174:715-21. [PMID: 19197002 DOI: 10.2353/ajpath.2009.080758] [Citation(s) in RCA: 253] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Stem cells hold great promise for regenerative medicine, but have remained elusive in many tissues because of a lack of adequate definitive markers. Progress in mouse genetics has provided the tools for characterization and validation of stem cell markers by functional and/or lineage tracing assays. The Wnt target gene Lgr5 has been recently identified as a novel stem cell marker of the intestinal epithelium and the hair follicle. In the intestine, Lgr5 is exclusively expressed in cycling crypt base columnar cells. Genetic lineage-tracing experiments revealed that crypt base columnar cells are capable of self-renewal and multipotency, thus representing genuine intestinal stem cells. In the stem cell niche of the murine hair follicle, Lgr5 is expressed in actively cycling cells. Transplantation and lineage tracing experiments have demonstrated that these Lgr5(+ve) cells maintain all cell lineages of the hair follicle throughout long periods of time and can build entire new hair follicles. Expression of Lgr5 in multiple other organs indicates that it may represent a global marker of adult stem cells. This review attempts to provide a comprehensive overview of the stem cell compartments in the intestine and skin with a focus on the cycling, yet long-lived and multipotent, Lgr5(+ve) stem cell populations.
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Affiliation(s)
- Andrea Haegebarth
- Hubrecht Institute and University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, The
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193
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Abstract
Several recent findings in stem cell biology have resulted in new opportunities for the treatment of reproductive disease. Endometrial regeneration can be driven by bone marrow derived stem cells. This finding has potential implications for the treatment of uterine disorders. It also supports a new theory for the etiology of endometriosis. The ovaries have been shown to contain stem cells that form oocytes in adults and can be cultured in vitro to develop mature oocytes. Stem cells from the fetus have been demonstrated to lead to microchimerism in the mother and implicated in several maternal diseases. Additionally the placenta may be another source of hematopoietic stem cell. Finally endometrial derived stem cells have been demonstrated to differentiate into non-reproductive tissues. While we are just beginning to understand stem cells and many key questions remain, the potential advantages of stem cells in reproductive biology and medicine are apparent.
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Affiliation(s)
- Hongling Du
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University, New Haven, Connecticut 06520, USA
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194
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Affiliation(s)
- Irene Cervelló
- Fundación IVI, Instituto Universitario IVI, Universidad de Valencia,
| | - Carlos Simón
- Centro de Investigación Príncipe Felipe, Valencia
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195
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Szlávik V, Szabó B, Vicsek T, Barabás J, Bogdán S, Gresz V, Varga G, O'Connell B, Vág J. Differentiation of primary human submandibular gland cells cultured on basement membrane extract. Tissue Eng Part A 2009; 14:1915-26. [PMID: 18721074 DOI: 10.1089/ten.tea.2007.0208] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
There is no effective treatment for the loss of functional salivary tissue after irradiation for head and neck cancer or the autoimmune disease Sjögren's syndrome. One possible approach is the regeneration of salivary glands from stem cells. The present study aimed to investigate whether small pieces of human submandiblar gland tissue contain elements necessary for the reconstruction of salivary rudiments in vitro via acinar and ductal cell differentiation. Primary submandibular gland (primary total human salivary gland; PTHSG) cells were isolated from human tissue and cultured in vitro using a new method in which single cells form an expanding epithelial monolayer on plastic substrates. Differentiation, morphology, number, and organization of these cells were then followed on basement membrane extract (BME) using RNA quantitation (amylase, claudin-1 (CLN1), CLN3, kallikrein, vimentin), immunohistochemistry (amylase and occludin), viability assay, and videomicroscopy. On the surface of BME, PTHSG cells formed acinotubular structures within 24 h, did not proliferate, and stained for amylase. In cultures derived from half of the donors, the acinar markers amylase and CLN3 were upregulated. The PTHSG culture model suggests that human salivary gland may be capable of regeneration via reorganization and differentiation and that basement membrane components play a crucial role in the morphological and functional differentiation of salivary cells.
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Affiliation(s)
- Vanda Szlávik
- Department of Oral Biology, Semmelweis University and Hungarian Academy of Sciences, Budapest, Hungary
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196
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Abstract
The intestinal epithelial lining plays a central role in the digestion and absorption of nutrients, but exists in a harsh luminal environment that necessitates continual renewal. This renewal process involves epithelial cell proliferation in the crypt base and later cell migration from the crypt base to the luminal surface. This process is dependent on multi-potent progenitor cells, or stem cells, located in each crypt. There are about 4 to 6 stem cells per crypt, and these stem cells are believed to generate distinct end-differentiated epithelial cell types, including absorptive cells, goblet cells, enteroendocrine cells and Paneth cells, while also maintaining their own progenitor cell state. Earlier studies suggested that intestinal stem cells were located either in the crypt base interspersed between the Paneth cells [i.e. crypt base columnar (CBC) cell model] or at an average position of 4 cells from the crypt base [i.e. label-retaining cells (LRC +4) model]. Recent studies have employed biomarkers in the in vivo mammalian state to more precisely evaluate the location of these progenitor cells in the intestinal crypt. Most notable of these novel markers are Lgr5, a gene that encodes a G-protein-coupled receptor with expression restricted to CBC cells, and Bmi 1, which encodes a chromatin remodeling protein expressed by LRC. These studies raise the possibility that there may be separate stem cell lines or different states of stem cell activation involved in the renewal of normal mammalian intestinal tract.
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197
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Abstract
Stem cells hold great promise for regenerative medicine but remain elusive in many tissues, including the small intestine, where it is well accepted that the epithelium is maintained by intestinal stem cells located in the crypts. The lack of established markers to prospectively identify intestinal stem cells has necessitated the use of indirect analysis, e.g. long-term label retention, which is based on the hypothesis that intestinal stem cells are slow-cycling. Several intestinal stem cell markers have been proposed, including Musashi-1, BMPR1alpha, phospho-PTEN, DCAMKL1, Eph receptors and integrins, but their validity, using functional and/or lineage tracing assays, has yet to be confirmed. Recently, Lgr5 has been identified by lineage tracing as an intestinal stem cell marker. In this review we summarize what is known about the currently reported intestinal stem cell markers and provide a rationale for developing model systems whereby intestinal stem cells can be functionally validated.
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Affiliation(s)
- Robert K Montgomery
- Division of Gastroenterology, Children's Hospital Boston, Department of Pediatrics, Harvard Medical School, Boston, MA, USA
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198
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Abstract
The concept that cancer might arise from a rare population of cells with stem cell-like properties was proposed 150 years ago. Increasing evidence during the past 2 decades suggests the existence of a small subgroup of cells in cancer that are responsible for tumor growth and proliferation. Stem cells have self-renewing properties; thus, they are appealing candidates for generating the malignant phenotype. Although the concept of stem cells in leukemia has received significant attention for more than the past decade, over the past several years, expression of several surface markers on cancer cells has led to identification of tumor-initiating cells in several solid tumors, including melanoma, brain, breast, prostate, liver, pancreatic, ovarian, and recently, colon cancer. This review will provide an update of the biologic basis of the stem cell model and possible targets for the treatment of colon cancer.
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Affiliation(s)
- Alexandra Pohl
- Division of Medical Oncology, University of Southern California, Norris Comprehensive Cancer Center, Keck School of Medicine, Los Angeles, CA 90033, USA
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199
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Abstract
The epithelium of the adult mammalian intestine is in a constant dialog with its underlying mesenchyme to direct progenitor proliferation, lineage commitment, terminal differentiation, and, ultimately, cell death. The epithelium is shaped into spatially distinct compartments that are dedicated to each of these events. While the intestinal epithelium represents the most vigorously renewing adult tissue in mammals, the stem cells that fuel this self-renewal process have been identified only recently. The unique epithelial anatomy makes the intestinal crypt one of the most accessible models for the study of adult stem cell biology. This review attempts to provide a comprehensive overview of four decades of research on crypt stem cells.
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Affiliation(s)
- Nick Barker
- Hubrecht Institute and University Medical Center Utrecht, Uppsalalaan 8, 3584CT Utrecht, the Netherlands
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200
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Dimitrov R, Timeva T, Kyurkchiev D, Stamenova M, Shterev A, Kostova P, Zlatkov V, Kehayov I, Kyurkchiev S. Characterization of clonogenic stromal cells isolated from human endometrium. Reproduction 2008; 135:551-8. [PMID: 18367513 DOI: 10.1530/rep-07-0428] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Human endometrium is an object of extensive restructuring and remodeling during the female reproductive life and it is quite tempting to assume that these periodic changes happen with the participation of cells that should have the basic characteristics of multipotent cells. The aim of this study was to search for the presence of cells with plastic adherence, clonogenicity, and differentiation in human endometrium. To this end, human endometrial stromal cells were cultured in vitro for more than 15 passages. Flow cytometry analysis of the cultured cells showed that they were positive for CD29, CD73 and CD90, which are considered to be the markers of cells with mesenchymal origin. The cells were negative for the hematopoietic cell markers (CD45, CD34, CD14, CD3, CD19, CD16/56, and HLA-DR). Further, it was shown that the cultured cells had 15% clonogenic efficiency and could be induced to differentiate into adipogenic cells containing typical lipid-rich vacuoles. These results demonstrate that the human endometrium contains a low number of cells with the characteristics of endometrial stromal stem/progenitor cells, which seem to belong to the family of the mesenchymal stem cells. It can be speculated that these cells are engaged into the monthly restructuring and remodeling of human endometrium.
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Affiliation(s)
- R Dimitrov
- Department of Immunochemistry, Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
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