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  1. Stem cells and niches: mechanisms that promote stem cell maintenance throughout life

    PubMed Central

    Morrison, Sean J.; Spradling, Allan C.

    2015-01-01

    Niches are local tissue microenvironments that maintain and regulate stem cells. Long-predicted from mammalian studies, these structures have recently been characterized within several invertebrate tissues using methods that reliably identify individual stem cells and their functional requirements. Although, similar single-cell resolution has not usually been achieved in mammalian tissues, principles likely to govern the behavior of niches in diverse organisms are beginning to emerge and considerable progress has been made elucidating the microenvironmental mechanisms that promote stem cell maintenance. These mechanisms may not only guide tissue homeostasis but when altered during adulthood likely contribute to aging and tumorigenesis. PMID:18295578

  2. Recruitment of mesenchymal stem cells into prostate tumours promotes metastasis.

    PubMed

    Jung, Younghun; Kim, Jin Koo; Shiozawa, Yusuke; Wang, Jingcheng; Mishra, Anjali; Joseph, Jeena; Berry, Janice E; McGee, Samantha; Lee, Eunsohl; Sun, Hongli; Wang, Jianhua; Jin, Taocong; Zhang, Honglai; Dai, Jinlu; Krebsbach, Paul H; Keller, Evan T; Pienta, Kenneth J; Taichman, Russell S

    2013-01-01

    Tumours recruit mesenchymal stem cells to facilitate healing, which induces their conversion into cancer-associated fibroblasts that facilitate metastasis. However, this process is poorly understood on the molecular level. Here we show that CXCL16, a ligand for CXCR6, facilitates mesenchymal stem cell or very small embryonic-like cells recruitment into prostate tumours. CXCR6 signalling stimulates the conversion of mesenchymal stem cells into cancer-associated fibroblasts, which secrete stromal-derived factor-1, also known as CXCL12. CXCL12 expressed by cancer-associated fibroblasts then binds to CXCR4 on tumour cells and induces an epithelial-to-mesenchymal transition, which ultimately promotes metastasis to secondary tumour sites. Our results provide the molecular basis for mesenchymal stem cell recruitment into tumours and how this process leads to tumour metastasis. PMID:23653207

  3. VEGF promotes tumorigenesis and angiogenesis of human glioblastoma stem cells

    SciTech Connect

    Oka, Naoki; Soeda, Akio . E-mail: ccd29400@nyc.odn.ne.jp; Inagaki, Akihito; Onodera, Masafumi; Maruyama, Hidekazu; Hara, Akira; Kunisada, Takahiro; Mori, Hideki; Iwama, Toru

    2007-08-31

    There is increasing evidence for the presence of cancer stem cells (CSCs) in malignant brain tumors, and these CSCs may play a pivotal role in tumor initiation, growth, and recurrence. Vascular endothelial growth factor (VEGF) promotes the proliferation of vascular endothelial cells (VECs) and the neurogenesis of neural stem cells. Using CSCs derived from human glioblastomas and a retrovirus expressing VEGF, we examined the effects of VEGF on the properties of CSCs in vitro and in vivo. Although VEGF did not affect the property of CSCs in vitro, the injection of mouse brains with VEGF-expressing CSCs led to the massive expansion of vascular-rich GBM, tumor-associated hemorrhage, and high morbidity, suggesting that VEGF promoted tumorigenesis via angiogenesis. These results revealed that VEGF induced the proliferation of VEC in the vascular-rich tumor environment, the so-called stem cell niche.

  4. Steroid signaling promotes stem cell maintenance in the Drosophila testis.

    PubMed

    Li, Yijie; Ma, Qing; Cherry, Christopher M; Matunis, Erika L

    2014-10-01

    Stem cell regulation by local signals is intensely studied, but less is known about the effects of hormonal signals on stem cells. In Drosophila, the primary steroid twenty-hydroxyecdysone (20E) regulates ovarian germline stem cells (GSCs) but was considered dispensable for testis GSC maintenance. Male GSCs reside in a microenvironment (niche) generated by somatic hub cells and adjacent cyst stem cells (CySCs). Here, we show that depletion of 20E from adult males by overexpressing a dominant negative form of the Ecdysone receptor (EcR) or its heterodimeric partner ultraspiracle (usp) causes GSC and CySC loss that is rescued by 20E feeding, uncovering a requirement for 20E in stem cell maintenance. EcR and USP are expressed, activated and autonomously required in the CySC lineage to promote CySC maintenance, as are downstream genes ftz-f1 and E75. In contrast, GSCs non-autonomously require ecdysone signaling. Global inactivation of EcR increases cell death in the testis that is rescued by expression of EcR-B2 in the CySC lineage, indicating that ecdysone signaling supports stem cell viability primarily through a specific receptor isoform. Finally, EcR genetically interacts with the NURF chromatin-remodeling complex, which we previously showed maintains CySCs. Thus, although 20E levels are lower in males than females, ecdysone signaling acts through distinct cell types and effectors to ensure both ovarian and testis stem cell maintenance. PMID:25093968

  5. Nanotopography Promotes Pancreatic Differentiation of Human Embryonic Stem Cells and Induced Pluripotent Stem Cells.

    PubMed

    Kim, Jong Hyun; Kim, Hyung Woo; Cha, Kyoung Je; Han, Jiyou; Jang, Yu Jin; Kim, Dong Sung; Kim, Jong-Hoon

    2016-03-22

    Although previous studies suggest that nanotopographical features influence properties and behaviors of stem cells, only a few studies have attempted to derive clinically useful somatic cells from human pluripotent stem cells using nanopatterned surfaces. In the present study, we report that polystyrene nanopore-patterned surfaces significantly promote the pancreatic differentiation of human embryonic and induced pluripotent stem cells. We compared different diameters of nanopores and showed that 200 nm nanopore-patterned surfaces highly upregulated the expression of PDX1, a critical transcription factor for pancreatic development, leading to an approximately 3-fold increase in the percentage of differentiating PDX1(+) pancreatic progenitors compared with control flat surfaces. Furthermore, in the presence of biochemical factors, 200 nm nanopore-patterned surfaces profoundly enhanced the derivation of pancreatic endocrine cells producing insulin, glucagon, or somatostatin. We also demonstrate that nanopore-patterned surface-induced upregulation of PDX1 is associated with downregulation of TAZ, suggesting the potential role of TAZ in nanopore-patterned surface-mediated mechanotransduction. Our study suggests that appropriate cytokine treatments combined with nanotopographical stimulation could be a powerful tool for deriving a high purity of desired cells from human pluripotent stem cells. PMID:26900863

  6. Purified Human Dental Pulp Stem Cells Promote Osteogenic Regeneration.

    PubMed

    Yasui, T; Mabuchi, Y; Toriumi, H; Ebine, T; Niibe, K; Houlihan, D D; Morikawa, S; Onizawa, K; Kawana, H; Akazawa, C; Suzuki, N; Nakagawa, T; Okano, H; Matsuzaki, Y

    2016-02-01

    Human dental pulp stem/progenitor cells (hDPSCs) are attractive candidates for regenerative therapy because they can be easily expanded to generate colony-forming unit-fibroblasts (CFU-Fs) on plastic and the large cell numbers required for transplantation. However, isolation based on adherence to plastic inevitably changes the surface marker expression and biological properties of the cells. Consequently, little is currently known about the original phenotypes of tissue precursor cells that give rise to plastic-adherent CFU-Fs. To better understand the in vivo functions and translational therapeutic potential of hDPSCs and other stem cells, selective cell markers must be identified in the progenitor cells. Here, we identified a dental pulp tissue-specific cell population based on the expression profiles of 2 cell-surface markers LNGFR (CD271) and THY-1 (CD90). Prospectively isolated, dental pulp-derived LNGFR(Low+)THY-1(High+) cells represent a highly enriched population of clonogenic cells--notably, the isolated cells exhibited long-term proliferation and multilineage differentiation potential in vitro. The cells also expressed known mesenchymal cell markers and promoted new bone formation to heal critical-size calvarial defects in vivo. These findings suggest that LNGFR(Low+)THY-1(High+) dental pulp-derived cells provide an excellent source of material for bone regenerative strategies. PMID:26494655

  7. Spirulina Promotes Stem Cell Genesis and Protects against LPS Induced Declines in Neural Stem Cell Proliferation

    PubMed Central

    Bachstetter, Adam D.; Jernberg, Jennifer; Schlunk, Andrea; Vila, Jennifer L.; Hudson, Charles; Cole, Michael J.; Shytle, R. Douglas; Tan, Jun; Sanberg, Paul R.; Sanberg, Cyndy D.; Borlongan, Cesario; Kaneko, Yuji; Tajiri, Naoki; Gemma, Carmelina; Bickford, Paula C.

    2010-01-01

    Adult stem cells are present in many tissues including, skin, muscle, adipose, bone marrow, and in the brain. Neuroinflammation has been shown to be a potent negative regulator of stem cell and progenitor cell proliferation in the neurogenic regions of the brain. Recently we demonstrated that decreasing a key neuroinflammatory cytokine IL-1β in the hippocampus of aged rats reversed the age-related cognitive decline and increased neurogenesis in the age rats. We also have found that nutraceuticals have the potential to reduce neuroinflammation, and decrease oxidative stress. The objectives of this study were to determine if spirulina could protect the proliferative potential of hippocampal neural progenitor cells from an acute systemic inflammatory insult of lipopolysaccharide (LPS). To this end, young rats were fed for 30 days a control diet or a diet supplemented with 0.1% spirulina. On day 28 the rats were given a single i.p. injection of LPS (1 mg/kg). The following day the rats were injected with BrdU (50 mg/kg b.i.d. i.p.) and were sacrificed 24 hours after the first injection of BrdU. Quantification of the BrdU positive cells in the subgranular zone of the dentate gyrus demonstrated a decrease in proliferation of the stem/progenitor cells in the hippocampus as a result of the LPS insult. Furthermore, the diet supplemented with spirulina was able to negate the LPS induced decrease in stem/progenitor cell proliferation. In a second set of studies we examined the effects of spirulina either alone or in combination with a proprietary formulation (NT-020) of blueberry, green tea, vitamin D3 and carnosine on the function of bone marrow and CD34+ cells in vitro. Spirulina had small effects on its own and more than additive effects in combination with NT-020 to promote mitochondrial respiration and/or proliferation of these cells in culture. When examined on neural stem cells in culture spirulina increased proliferation at baseline and protected against the negative

  8. Propranolol Promotes Accelerated and Dysregulated Adipogenesis in Hemangioma Stem Cells

    PubMed Central

    England, Ryan W.; Hardy, Krista L.; Kitajewski, Alex M.; Wong, Alvin; Kitajewski, Jan K.; Shawber, Carrie J.; Wu, June K.

    2014-01-01

    Background Infantile hemangiomas are the most common tumor of infancy, yet there are no FDA-approved therapeutics to date. Recently, the non-selective beta-adrenergic-blocker propranolol has been shown to be a safe and effective means of treating infantile hemangiomas, though its mechanism has yet to be elucidated. We have previously demonstrated that propranolol induces early and incomplete adipogenesis in stem cells derived from hemangiomas. We hypothesize that propranolol promotes dysregulated adipogenesis via the improper regulation of adipogenic genes. Methods Hemangioma stem cells isolated from resected infantile hemangioma specimens were treated with adipogenic medium for 1 or 4 days in either propranolol or vehicle. Cell death was measured by the incorporation of annexin V and propidium iodide by flow cytometry. Adipogenesis was assessed by visualizing lipid droplet formation by Oil Red O staining. Pro-adipogenic genes C/EBPβ, C/EBPβ, C/EBPδ, PPARδ, PPARγ, RXRα, and RXRγ were analyzed by quantitative reverse transcription and polymerase chain reaction. Results Hemangioma stem cells treated with propranolol increased lipid droplet formation compared to vehicle-treated cells indicating increased adipogenesis. Cell death as measured by FACS analysis indicated that the propranolol-treated cells died due to necrosis and not apoptosis. During adipogenesis, transcript levels of PPARδ, PPARγ, C/EBPβ, and C/EBPδ were significantly increased (p < 0.01) in propranolol-treated cells relative to control cells. In contrast, RXRα and RXRγ levels were significantly decreased (p < 0.05), and C/EBPα, a gene required for terminal adipocyte differentiation, was strongly suppressed by propranolol when compared to vehicle-treated cells (p < 0.01). Conclusions In hemangioma stem cells, propranolol accelerated dysregulated adipogenic differentiation characterized by improper adipogenic gene expression. Consistent with accelerated adipogenesis, propranolol

  9. Epigenetic modulators promote mesenchymal stem cell phenotype switches.

    PubMed

    Alexanian, Arshak R

    2015-07-01

    Discoveries in recent years have suggested that some tissue specific adult stem cells in mammals might have the ability to differentiate into cell types from different germ layers. This phenomenon has been referred to as stem cell transdifferentiation or plasticity. Despite controversy, the current consensus holds that transdifferentiation does occur in mammals, but only within a limited range. Understanding the mechanisms that underlie the switches in phenotype and development of the methods that will promote such type of conversions can open up endless possibilities for regenerative medicine. Epigenetic control contributes to various processes that lead to cellular plasticity and DNA and histone covalent modifications play a key role in these processes. Recently, we have been able to convert human mesenchymal stem cells (hMSCs) into neural-like cells by exposing cells to epigenetic modifiers and neural inducing factors. The goal of this study was to investigate the stability and plasticity of these transdifferentiated cells. To this end, neurally induced MSCs (NI-hMSCs) were exposed to adipocyte inducing factors. Grown for 24-48 h in fat induction media NI-hMSCs reversed their morphology into fibroblast-like cells and regained their proliferative properties. After 3 weeks approximately 6% of hMSCs differentiated into multilocular or plurivacuolar adipocyte cells that demonstrated by Oil Red O staining. Re-exposure of these cultures or the purified adipocytes to neural induction medium induced the cells to re-differentiate into neuronal-like cells. These data suggest that cell plasticity can be manipulated by the combination of small molecule modulators of chromatin modifying enzymes and specific cell signaling pathways. PMID:25936755

  10. Recruitment of Mesenchymal Stem Cells Into Prostate Tumors Promotes Metastasis

    PubMed Central

    Jung, Younghun; Kim, Jin Koo; Shiozawa, Yusuke; Wang, Jingcheng; Mishra, Anjali; Joseph, Jeena; Berry, Janice E.; McGee, Samantha; Lee, Eunsohl; Sun, Hongli; Wang, Jianhua; Jin, Taocong; Zhang, Honglai; Dai, Jinlu; Krebsbach, Paul H.; Keller, Evan T.; Pienta, Kenneth J.; Taichman, Russell S.

    2013-01-01

    Tumors recruit mesenchymal stem cells (MSCs) to facilitate healing, which induces their conversion into cancer-associated fibroblasts that facilitate metastasis. However, this process is poorly understood on the molecular level. Here we show that the CXCR6 ligand CXCL16 facilitates MSC or Very Small Embryonic-Like (VSEL) cells recruitment into prostate tumors. CXCR6 signaling stimulates the conversion of MSCs into cancer-associated fibroblasts, which secrete stromal-derived factor-1, also known as CXCL12. CXCL12 expressed by cancer-associated fibroblasts then binds to CXCR4 on tumor cells and induces an epithelial to mesenchymal transition, which ultimately promotes metastasis to secondary tumor sites. Our results provide the molecular basis for MSC recruitment into tumors and how this process leads to tumor metastasis. PMID:23653207

  11. Human neural stem cells promote proliferation of endogenous neural stem cells and enhance angiogenesis in ischemic rat brain

    PubMed Central

    Ryu, Sun; Lee, Seung-Hoon; Kim, Seung U.; Yoon, Byung-Woo

    2016-01-01

    Transplantation of human neural stem cells into the dentate gyrus or ventricle of rodents has been reportedly to enhance neurogenesis. In this study, we examined endogenous stem cell proliferation and angiogenesis in the ischemic rat brain after the transplantation of human neural stem cells. Focal cerebral ischemia in the rat brain was induced by middle cerebral artery occlusion. Human neural stem cells were transplanted into the subventricular zone. The behavioral performance of human neural stem cells-treated ischemic rats was significantly improved and cerebral infarct volumes were reduced compared to those in untreated animals. Numerous transplanted human neural stem cells were alive and preferentially localized to the ipsilateral ischemic hemisphere. Furthermore, 5-bromo-2′-deoxyuridine-labeled endogenous neural stem cells were observed in the subventricular zone and hippocampus, where they differentiated into cells immunoreactive for the neural markers doublecortin, neuronal nuclear antigen NeuN, and astrocyte marker glial fibrillary acidic protein in human neural stem cells-treated rats, but not in the untreated ischemic animals. The number of 5-bromo-2′-deoxyuridine-positive ⁄ anti-von Willebrand factor-positive proliferating endothelial cells was higher in the ischemic boundary zone of human neural stem cells-treated rats than in controls. Finally, transplantation of human neural stem cells in the brains of rats with focal cerebral ischemia promoted the proliferation of endogenous neural stem cells and their differentiation into mature neural-like cells, and enhanced angiogenesis. This study provides valuable insights into the effect of human neural stem cell transplantation on focal cerebral ischemia, which can be applied to the development of an effective therapy for stroke. PMID:27073384

  12. Interleukin-22 Promotes Intestinal Stem Cell-Mediated Epithelial Regeneration

    PubMed Central

    Dudakov, Jarrod A.; Jenq, Robert R.; Velardi, Enrico; Young, Lauren F.; Smith, Odette M.; Lawrence, Gillian; Ivanov, Juliet A.; Fu, Ya-Yuan; Takashima, Shuichiro; Hua, Guoqiang; Martin, Maria L.; O'Rourke, Kevin P.; Lo, Yuan-Hung; Mokry, Michal; Romera-Hernandez, Monica; Cupedo, Tom; Dow, Lukas; Nieuwenhuis, Edward E.; Shroyer, Noah F.; Liu, Chen; Kolesnick, Richard

    2015-01-01

    Epithelial regeneration is critical for barrier maintenance and organ function after intestinal injury. The intestinal stem cell (ISC) niche provides Wnt, Notch, and epidermal growth factor (EGF) signals supporting Lgr5+ crypt base columnar ISCs for normal epithelial maintenance1,2. However, little is known about the regulation of the ISC compartment after tissue damage. Utilizing ex vivo organoid cultures, we provide evidence that innate lymphoid cells (ILCs), potent producers of Interleukin-22 (IL-22) after intestinal injury3,4, increased the growth of murine small intestine (SI) organoids in an IL-22-dependent fashion. Recombinant IL-22 directly targeted ISCs, augmenting the growth of both murine and human intestinal organoids, increasing proliferation, and promoting ISC expansion. IL-22 induced Stat3 phosphorylation in Lgr5+ ISCs, and Stat3 was critical for both organoid formation and IL-22-mediated regeneration. Treatment with IL-22 in vivo after murine allogeneic bone marrow transplantation (BMT) enhanced recovery of ISCs, increased epithelial regeneration, and reduced intestinal pathology and mortality from graft vs. host disease (GVHD). Atoh1-deficient organoid culture demonstrated that IL-22 induced epithelial regeneration independent of the Paneth cell niche. Our findings reveal a fundamental mechanism by which the immune system is able to support intestinal epithelium, activating ISCs to promote regeneration. PMID:26649819

  13. Interleukin-22 promotes intestinal-stem-cell-mediated epithelial regeneration.

    PubMed

    Lindemans, Caroline A; Calafiore, Marco; Mertelsmann, Anna M; O'Connor, Margaret H; Dudakov, Jarrod A; Jenq, Robert R; Velardi, Enrico; Young, Lauren F; Smith, Odette M; Lawrence, Gillian; Ivanov, Juliet A; Fu, Ya-Yuan; Takashima, Shuichiro; Hua, Guoqiang; Martin, Maria L; O'Rourke, Kevin P; Lo, Yuan-Hung; Mokry, Michal; Romera-Hernandez, Monica; Cupedo, Tom; Dow, Lukas E; Nieuwenhuis, Edward E; Shroyer, Noah F; Liu, Chen; Kolesnick, Richard; van den Brink, Marcel R M; Hanash, Alan M

    2015-12-24

    Epithelial regeneration is critical for barrier maintenance and organ function after intestinal injury. The intestinal stem cell (ISC) niche provides Wnt, Notch and epidermal growth factor (EGF) signals supporting Lgr5(+) crypt base columnar ISCs for normal epithelial maintenance. However, little is known about the regulation of the ISC compartment after tissue damage. Using ex vivo organoid cultures, here we show that innate lymphoid cells (ILCs), potent producers of interleukin-22 (IL-22) after intestinal injury, increase the growth of mouse small intestine organoids in an IL-22-dependent fashion. Recombinant IL-22 directly targeted ISCs, augmenting the growth of both mouse and human intestinal organoids, increasing proliferation and promoting ISC expansion. IL-22 induced STAT3 phosphorylation in Lgr5(+) ISCs, and STAT3 was crucial for both organoid formation and IL-22-mediated regeneration. Treatment with IL-22 in vivo after mouse allogeneic bone marrow transplantation enhanced the recovery of ISCs, increased epithelial regeneration and reduced intestinal pathology and mortality from graft-versus-host disease. ATOH1-deficient organoid culture demonstrated that IL-22 induced epithelial regeneration independently of the Paneth cell niche. Our findings reveal a fundamental mechanism by which the immune system is able to support the intestinal epithelium, activating ISCs to promote regeneration. PMID:26649819

  14. Hymyc1 Downregulation Promotes Stem Cell Proliferation in Hydra vulgaris

    PubMed Central

    Ambrosone, Alfredo; Marchesano, Valentina; Tino, Angela; Hobmayer, Bert; Tortiglione, Claudia

    2012-01-01

    Hydra is a unique model for studying the mechanisms underlying stem cell biology. The activity of the three stem cell lineages structuring its body constantly replenishes mature cells lost due to normal tissue turnover. By a poorly understood mechanism, stem cells are maintained through self-renewal while concomitantly producing differentiated progeny. In vertebrates, one of many genes that participate in regulating stem cell homeostasis is the protooncogene c-myc, which has been recently identified also in Hydra, and found expressed in the interstitial stem cell lineage. In the present paper, by developing a novel strategy of RNA interference-mediated gene silencing (RNAi) based on an enhanced uptake of small interfering RNAi (siRNA), we provide molecular and biological evidence for an unexpected function of the Hydra myc gene (Hymyc1) in the homeostasis of the interstitial stem cell lineage. We found that Hymyc1 inhibition impairs the balance between stem cell self renewal/differentiation, as shown by the accumulation of stem cell intermediate and terminal differentiation products in genetically interfered animals. The identical phenotype induced by the 10058-F4 inhibitor, a disruptor of c-Myc/Max dimerization, demonstrates the specificity of the RNAi approach. We show the kinetic and the reversible feature of Hymyc1 RNAi, together with the effects displayed on regenerating animals. Our results show the involvement of Hymyc1 in the control of interstitial stem cell dynamics, provide new clues to decipher the molecular control of the cell and tissue plasticity in Hydra, and also provide further insights into the complex myc network in higher organisms. The ability of Hydra cells to uptake double stranded RNA and to trigger a RNAi response lays the foundations of a comprehensive analysis of the RNAi response in Hydra allowing us to track back in the evolution and the origin of this process. PMID:22292012

  15. Calcium phosphate surfaces promote osteogenic differentiation of mesenchymal stem cells

    PubMed Central

    Müller, Petra; Bulnheim, Ulrike; Diener, Annette; Lüthen, Frank; Teller, Marianne; Klinkenberg, Ernst-Dieter; Neumann, Hans-Georg; Nebe, Barbara; Liebold, Andreas; Steinhoff, Gustav; Rychly, Joachim

    2008-01-01

    Abstract Although studies in vivo revealed promising results in bone regeneration after implantation of scaffolds together with osteogenic progenitor cells, basic questions remain how material surfaces control the biology of mesenchymal stem cells (MSC). We used human MSC derived from bone marrow and studied the osteogenic differentiation on calcium phosphate surfaces. In osteogenic differentiation medium MSC differentiated to osteoblasts on hydroxyapatite and BONITmatrix®, a degradable xerogel composite, within 14 days. Cells revealed a higher alkaline phosphatase (ALP) activity and increased RNA expression of collagen I and osteocalcin using real-time RTPCR compared with cells on tissue culture plastic. To test whether material surface characteristics alone are able to stimulate osteogenic differentiation, MSC were cultured on the materials in expansion medium without soluble additives for osteogenic differentiation. Indeed, cells on calcium phosphate without osteogenic differentiation additives developed to osteoblasts as shown by increased ALP activity and expression of osteogenic genes, which was not the case on tissue culture plastic. Because we reasoned that the stimulating effect on osteogenesis by calcium phosphate surfaces depends on an altered cell–extracellular matrix interaction we studied the dynamic behaviour of focal adhesions using cells transfected with GFP labelled vinculin. On BONITmatrix®, an increased mobility of focal adhesions was observed compared with cells on tissue culture plastic. In conclusion, calcium phosphate surfaces are able to drive MSC to osteoblasts in the absence of osteogenic differentiation supplements in the medium. An altered dynamic behaviour of focal adhesions on calcium phosphate surfaces might be involved in the molecular mechanisms which promote osteogenic differentiation. PMID:18366455

  16. Tenuigenin promotes proliferation and differentiation of hippocampal neural stem cells.

    PubMed

    Chen, Yujing; Huang, Xiaobo; Chen, Wenqiang; Wang, Ningqun; Li, Lin

    2012-04-01

    The present study was to investigate the influence of tenuigenin, an active ingredient of Polygala tenuifolia Willd, on the proliferation and differentiation of hippocampal neural stem cells in vitro. Tenuigenin was added to a neurosphere culture and neurosphere growth was measured using MTT assay. The influence of tenuigenin on the proliferation of neural progenitors was examined by Clone forming assay and BrdU detection. In addition, the differentiation of neural stem cells was compared using immunocytochemistry for β III-tubulin and GFAP. The results showed that addition of tenuigenin to the neural stem cell medium increased the number of newly formed neurospheres. More neurons were also obtained when tenuigenin was added in the differentiation medium. These findings suggest that tenuigenin is involved in regulating the proliferation and differentiation of hippocampal neural stem cells. This result may be one of the underlying reasons for tenuigenin's nootropic and anti-aging effects. PMID:22179853

  17. Intravenous transplantation of bone marrow mesenchymal stem cells promotes neural regeneration after traumatic brain injury

    PubMed Central

    Anbari, Fatemeh; Khalili, Mohammad Ali; Bahrami, Ahmad Reza; Khoradmehr, Arezoo; Sadeghian, Fatemeh; Fesahat, Farzaneh; Nabi, Ali

    2014-01-01

    To investigate the supplement of lost nerve cells in rats with traumatic brain injury by intravenous administration of allogenic bone marrow mesenchymal stem cells, this study established a Wistar rat model of traumatic brain injury by weight drop impact acceleration method and administered 3 × 106 rat bone marrow mesenchymal stem cells via the lateral tail vein. At 14 days after cell transplantation, bone marrow mesenchymal stem cells differentiated into neurons and astrocytes in injured rat cerebral cortex and rat neurological function was improved significantly. These findings suggest that intravenously administered bone marrow mesenchymal stem cells can promote nerve cell regeneration in injured cerebral cortex, which supplement the lost nerve cells. PMID:25206912

  18. Adipose-derived mesenchymal stem cells promote cell proliferation and invasion of epithelial ovarian cancer

    SciTech Connect

    Chu, Yijing; Tang, Huijuan; Guo, Yan; Guo, Jing; Huang, Bangxing; Fang, Fang; Cai, Jing Wang, Zehua

    2015-09-10

    Adipose-derived mesenchymal stem cell (ADSC) is an important component of tumor microenvironment. However, whether ADSCs have a hand in ovarian cancer progression remains unclear. In this study, we investigated the impact of human ADSCs derived from the omentum of normal donors on human epithelial ovarian cancer (EOC) cells in vitro and in vivo. Direct and indirect co-culture models including ADSCs and human EOC cell lines were established and the effects of ADSCs on EOC cell proliferation were evaluated by EdU incorporation and flow cytometry. Transwell migration assays and detection of MMPs were performed to assess the invasion activity of EOC cells in vitro. Mouse models were established by intraperitoneal injection of EOC cells with or without concomitant ADSCs to investigate the role of ADSCs in tumor progression in vivo. We found that ADSCs significantly promoted proliferation and invasion of EOC cells in both direct and indirect co-culture assays. In addition, after co-culture with ADSCs, EOC cells secreted higher levels of matrix metalloproteinases (MMPs), and inhibition of MMP2 and MMP9 partially relieved the tumor-promoting effects of ADSCs in vitro. In mouse xenograft models, we confirmed that ADSCs promoted EOC growth and metastasis and elevated the expression of MMP2 and MMP9. Our findings indicate that omental ADSCs play a promotive role during ovarian cancer progression. - Highlights: • Omental adipose derived stem cells enhanced growth and invasion properties of ovarian cancer cells. • Adipose derived stem cells promoted the growth and metastasis of ovarian cancer in mice models. • Adipose derived stem cells promoted MMPs expression and secretion of ovarian cancer cells. • Elevated MMPs mediated the tumor promoting effects of ADSCs.

  19. Stem Cells

    MedlinePlus

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  20. Stem Cells

    MedlinePlus

    Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  1. Adiponectin Promotes Human Jaw Bone Marrow Stem Cell Osteogenesis.

    PubMed

    Pu, Y; Wu, H; Lu, S; Hu, H; Li, D; Wu, Y; Tang, Z

    2016-07-01

    Human jaw bone marrow mesenchymal stem cells (h-JBMMSCs) are multipotent progenitor cells with osteogenic differentiation potential. The relationship between adiponectin (APN) and the metabolism of h-JBMMSCs has not been fully elucidated, and the underlying mechanism remains unclear. The aim of the study was to investigate the effect and mechanism of APN on h-JBMMSC metabolism. h-JBMMSCs were obtained from the primary culture of human jaw bones and treated with or without APN (1 µg/mL). Osteogenesis-related gene expression was evaluated by real-time polymerase chain reaction (PCR), alkaline phosphatase (ALP) activity assay, and enzyme-linked immunosorbent assay (ELISA). To further investigate the signaling pathway, mechanistic studies were performed using Western blotting, immunofluorescence, lentiviral transduction, and SB202190 (a specific p38 inhibitor). Alizarin Red staining showed that APN promoted h-JBMMSC osteogenesis. Real-time PCR, ALP assay, and ELISA showed that ALP, osteocalcin (OCN), osteopontin, and integrin-binding sialoprotein were up-regulated in APN-treated cells compared to untreated controls. Immunofluorescence revealed that adaptor protein containing a pleckstrin homology domain, phosphotyrosine domain, and leucine zipper motif (APPL1) translocated from the nucleus to the cytoplasm with APN treatment. Additionally, the phosphorylation of p38 mitogen-activated protein kinase (MAPK) increased over time with APN treatment. Moreover, knockdown of APPL1 or p38 MAPK inhibition blocked the expression of APN-induced calcification-related genes including ALP, Runt-related transcription factor 2 (RUNX2), and OCN. Furthermore, Alizarin Red staining of calcium nodes was not increased by the knockdown of APPL1 or p38 inhibition. Our data suggest that this regulation is mediated through the APPL1-p38 MAPK signaling pathway. These findings collectively provide evidence that APN induces the osteogenesis of h-JBMMSCs through APPL1-mediated p38 MAPK activation

  2. Graphene Oxide promotes embryonic stem cell differentiation to haematopoietic lineage

    PubMed Central

    Garcia-Alegria, Eva; Iluit, Maria; Stefanska, Monika; Silva, Claudio; Heeg, Sebastian; Kimber, Susan J.; Kouskoff, Valerie; Lacaud, Georges; Vijayaraghavan, Aravind; Batta, Kiran

    2016-01-01

    Pluripotent stem cells represent a promising source of differentiated tissue-specific stem and multipotent progenitor cells for regenerative medicine and drug testing. The realisation of this potential relies on the establishment of robust and reproducible protocols of differentiation. Several reports have highlighted the importance of biomaterials in assisting directed differentiation. Graphene oxide (GO) is a novel material that has attracted increasing interest in the field of biomedicine. In this study, we demonstrate that GO coated substrates significantly enhance the differentiation of mouse embryonic stem (ES) cells to both primitive and definitive haematopoietic cells. GO does not affect cell proliferation or survival of differentiated cells but rather enhances the transition of haemangioblasts to haemogenic endothelial cells, a key step during haematopoietic specification. Importantly, GO also improves, in addition to murine, human ES cell differentiation to blood cells. Taken together, our study reveals a positive role for GO in haematopoietic differentiation and suggests that further functionalization of GO could represent a valid strategy for the generation of large numbers of functional blood cells. Producing these cells would accelerate haematopoietic drug toxicity testing and treatment of patients with blood disorders or malignancies. PMID:27197878

  3. Graphene Oxide promotes embryonic stem cell differentiation to haematopoietic lineage.

    PubMed

    Garcia-Alegria, Eva; Iluit, Maria; Stefanska, Monika; Silva, Claudio; Heeg, Sebastian; Kimber, Susan J; Kouskoff, Valerie; Lacaud, Georges; Vijayaraghavan, Aravind; Batta, Kiran

    2016-01-01

    Pluripotent stem cells represent a promising source of differentiated tissue-specific stem and multipotent progenitor cells for regenerative medicine and drug testing. The realisation of this potential relies on the establishment of robust and reproducible protocols of differentiation. Several reports have highlighted the importance of biomaterials in assisting directed differentiation. Graphene oxide (GO) is a novel material that has attracted increasing interest in the field of biomedicine. In this study, we demonstrate that GO coated substrates significantly enhance the differentiation of mouse embryonic stem (ES) cells to both primitive and definitive haematopoietic cells. GO does not affect cell proliferation or survival of differentiated cells but rather enhances the transition of haemangioblasts to haemogenic endothelial cells, a key step during haematopoietic specification. Importantly, GO also improves, in addition to murine, human ES cell differentiation to blood cells. Taken together, our study reveals a positive role for GO in haematopoietic differentiation and suggests that further functionalization of GO could represent a valid strategy for the generation of large numbers of functional blood cells. Producing these cells would accelerate haematopoietic drug toxicity testing and treatment of patients with blood disorders or malignancies. PMID:27197878

  4. Cinnamtannin B-1 Promotes Migration of Mesenchymal Stem Cells and Accelerates Wound Healing in Mice.

    PubMed

    Fujita, Kosuke; Kuge, Katsunori; Ozawa, Noriyasu; Sahara, Shunya; Zaiki, Kaori; Nakaoji, Koichi; Hamada, Kazuhiko; Takenaka, Yukiko; Tanahashi, Takao; Tamai, Katsuto; Kaneda, Yasufumi; Maeda, Akito

    2015-01-01

    Substances that enhance the migration of mesenchymal stem cells to damaged sites have the potential to improve the effectiveness of tissue repair. We previously found that ethanol extracts of Mallotus philippinensis bark promoted migration of mesenchymal stem cells and improved wound healing in a mouse model. We also demonstrated that bark extracts contain cinnamtannin B-1, a flavonoid with in vitro migratory activity against mesenchymal stem cells. However, the in vivo effects of cinnamtannin B-1 on the migration of mesenchymal stem cells and underlying mechanism of this action remain unknown. Therefore, we examined the effects of cinnamtannin B-1 on in vivo migration of mesenchymal stem cells and wound healing in mice. In addition, we characterized cinnamtannin B-1-induced migration of mesenchymal stem cells pharmacologically and structurally. The mobilization of endogenous mesenchymal stem cells into the blood circulation was enhanced in cinnamtannin B-1-treated mice as shown by flow cytometric analysis of peripheral blood cells. Whole animal imaging analysis using luciferase-expressing mesenchymal stem cells as a tracer revealed that cinnamtannin B-1 increased the homing of mesenchymal stem cells to wounds and accelerated healing in a diabetic mouse model. Additionally, the cinnamtannin B-1-induced migration of mesenchymal stem cells was pharmacologically susceptible to inhibitors of phosphatidylinositol 3-kinase, phospholipase C, lipoxygenase, and purines. Furthermore, biflavonoids with similar structural features to cinnamtannin B-1 also augmented the migration of mesenchymal stem cells by similar pharmacological mechanisms. These results demonstrate that cinnamtannin B-1 promoted mesenchymal stem cell migration in vivo and improved wound healing in mice. Furthermore, the results reveal that cinnamtannin B-1-induced migration of mesenchymal stem cells may be mediated by specific signaling pathways, and the flavonoid skeleton may be relevant to its effects on

  5. Cinnamtannin B-1 Promotes Migration of Mesenchymal Stem Cells and Accelerates Wound Healing in Mice

    PubMed Central

    Fujita, Kosuke; Kuge, Katsunori; Ozawa, Noriyasu; Sahara, Shunya; Zaiki, Kaori; Nakaoji, Koichi; Hamada, Kazuhiko; Takenaka, Yukiko; Tanahashi, Takao; Tamai, Katsuto; Kaneda, Yasufumi; Maeda, Akito

    2015-01-01

    Substances that enhance the migration of mesenchymal stem cells to damaged sites have the potential to improve the effectiveness of tissue repair. We previously found that ethanol extracts of Mallotus philippinensis bark promoted migration of mesenchymal stem cells and improved wound healing in a mouse model. We also demonstrated that bark extracts contain cinnamtannin B-1, a flavonoid with in vitro migratory activity against mesenchymal stem cells. However, the in vivo effects of cinnamtannin B-1 on the migration of mesenchymal stem cells and underlying mechanism of this action remain unknown. Therefore, we examined the effects of cinnamtannin B-1 on in vivo migration of mesenchymal stem cells and wound healing in mice. In addition, we characterized cinnamtannin B-1-induced migration of mesenchymal stem cells pharmacologically and structurally. The mobilization of endogenous mesenchymal stem cells into the blood circulation was enhanced in cinnamtannin B-1-treated mice as shown by flow cytometric analysis of peripheral blood cells. Whole animal imaging analysis using luciferase-expressing mesenchymal stem cells as a tracer revealed that cinnamtannin B-1 increased the homing of mesenchymal stem cells to wounds and accelerated healing in a diabetic mouse model. Additionally, the cinnamtannin B-1-induced migration of mesenchymal stem cells was pharmacologically susceptible to inhibitors of phosphatidylinositol 3-kinase, phospholipase C, lipoxygenase, and purines. Furthermore, biflavonoids with similar structural features to cinnamtannin B-1 also augmented the migration of mesenchymal stem cells by similar pharmacological mechanisms. These results demonstrate that cinnamtannin B-1 promoted mesenchymal stem cell migration in vivo and improved wound healing in mice. Furthermore, the results reveal that cinnamtannin B-1-induced migration of mesenchymal stem cells may be mediated by specific signaling pathways, and the flavonoid skeleton may be relevant to its effects on

  6. Sertoli cells promote proliferation of bone marrow-derived mesenchymal stem cells in co-culture.

    PubMed

    Zhang, Fenxi; Lu, Ming; Liu, Hengxing; Ren, Tongming; Miao, Yingying; Wang, Jingjing

    2016-05-01

    Bone marrow-derived mesenchymal stem cells (BMSCs) are a major source for cell transplantation. The proliferative ability of BMSCs is an important determinant of the efficiency of transplant therapy. Sertoli cells are "nurse" cells for development of sperm cells. Our recent study showed that Sertoli cells promoted proliferation of human umbilical cord mesenchymal stem cells (hUCMSCs) in co-culture. Studies by other groups also showed that Sertoli cells promoted growth of endothelial cells and neural stem cells. In this study, we investigated the effect of Sertoli cells on proliferation of BMSCs. Our results showed that Sertoli cells in co-culture significantly enhanced proliferation of BMSCs (P < 0.01). Moreover, co-culture with Sertoli cells also markedly increased mRNA and/or protein expressions of Mdm2, p-Akt and Cyclin D1, and decreased p53 expression in BMSCs (P < 0.01 or < 0.05). These findings indicate that Sertoli cells have the potential to enhance proliferation of BMSCs. PMID:27319049

  7. IGFBP2 promotes glioma tumor stem cell expansion and survival

    SciTech Connect

    Hsieh, David; Hsieh, Antony; Stea, Baldassarre; Ellsworth, Ron

    2010-06-25

    IGFBP2 is overexpressed in the most common brain tumor, glioblastoma (GBM), and its expression is inversely correlated to GBM patient survival. Previous reports have demonstrated a role for IGFBP2 in glioma cell invasion and astrocytoma development. However, the function of IGFBP2 in the restricted, self-renewing, and tumorigenic GBM cell population comprised of tumor-initiating stem cells has yet to be determined. Herein we demonstrate that IGFBP2 is overexpressed within the stem cell compartment of GBMs and is integral for the clonal expansion and proliferative properties of glioma stem cells (GSCs). In addition, IGFBP2 inhibition reduced Akt-dependent GSC genotoxic and drug resistance. These results suggest that IGFBP2 is a selective malignant factor that may contribute significantly to GBM pathogenesis by enriching for GSCs and mediating their survival. Given the current dearth of selective molecular targets against GSCs, we anticipate our results to be of high therapeutic relevance in combating the rapid and lethal course of GBM.

  8. Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival

    PubMed Central

    Tinkum, Kelsey L.; Stemler, Kristina M.; White, Lynn S.; Loza, Andrew J.; Jeter-Jones, Sabrina; Michalski, Basia M.; Kuzmicki, Catherine; Pless, Robert; Stappenbeck, Thaddeus S.; Piwnica-Worms, David; Piwnica-Worms, Helen

    2015-01-01

    Short-term fasting protects mice from lethal doses of chemotherapy through undetermined mechanisms. Herein, we demonstrate that fasting preserves small intestinal (SI) architecture by maintaining SI stem cell viability and SI barrier function following exposure to high-dose etoposide. Nearly all SI stem cells were lost in fed mice, whereas fasting promoted sufficient SI stem cell survival to preserve SI integrity after etoposide treatment. Lineage tracing demonstrated that multiple SI stem cell populations, marked by Lgr5, Bmi1, or HopX expression, contributed to fasting-induced survival. DNA repair and DNA damage response genes were elevated in SI stem/progenitor cells of fasted etoposide-treated mice, which importantly correlated with faster resolution of DNA double-strand breaks and less apoptosis. Thus, fasting preserved SI stem cell viability as well as SI architecture and barrier function suggesting that fasting may reduce host toxicity in patients undergoing dose intensive chemotherapy. PMID:26644583

  9. Endothelial cell-initiated signaling promotes the survival and self-renewal of cancer stem cells

    PubMed Central

    Krishnamurthy, Sudha; Dong, Zhihong; Vodopyanov, Dmitry; Imai, Atsushi; Helman, Joseph I.; Prince, Mark E.; Wicha, Max S.; Nör, Jacques E.

    2010-01-01

    Recent studies have demonstrated that cancer stem cells play an important role in the pathobiology of head and neck squamous cell carcinomas (HNSCC). However, little is known about functional interactions between head and neck cancer stem-like cells (CSC) and surrounding stromal cells. Here, we used Aldehyde Dehydrogenase activity and CD44 expression to sort putative stem cells from primary human HNSCC. Implantation of 1,000 CSC (ALDH+CD44+Lin−) led to tumors in 13 (out of 15) mice, while 10,000 non-cancer stem cells (NCSC; ALDH−CD44−Lin−) resulted in 2 tumors in 15 mice. These data demonstrated that ALDH and CD44 select a sub-population of cells that are highly tumorigenic. The ability to self-renew was confirmed by the observation that ALDH+CD44+Lin− cells sorted from human HNSCC formed more spheroids (orospheres) in 3-D agarose matrices or ultra-low attachment plates than controls and were serially passaged in vivo. We observed that approximately 80% of the CSC were located in close proximity (within 100-µm radius) of blood vessels in human tumors, suggesting the existence of perivascular niches in HNSCC. In vitro studies demonstrated that endothelial cell-secreted factors promoted self-renewal of CSC, as demonstrated by the upregulation of Bmi-1 expression and the increase in the number of orospheres as compared to controls. Notably, selective ablation of tumor-associated endothelial cells stably transduced with a caspase-based artificial death switch (iCaspase-9) caused a marked reduction in the fraction of CSC in xenograft tumors. Collectively, these findings indicate that endothelial cell-initiated signaling can enhance the survival and self-renewal of head and neck cancer stem cells. PMID:21098716

  10. Lin-28 promotes symmetric stem cell division and drives adaptive growth in the adult Drosophila intestine.

    PubMed

    Chen, Ching-Huan; Luhur, Arthur; Sokol, Nicholas

    2015-10-15

    Stem cells switch between asymmetric and symmetric division to expand in number as tissues grow during development and in response to environmental changes. The stem cell intrinsic proteins controlling this switch are largely unknown, but one candidate is the Lin-28 pluripotency factor. A conserved RNA-binding protein that is downregulated in most animals as they develop from embryos to adults, Lin-28 persists in populations of adult stem cells. Its function in these cells has not been previously characterized. Here, we report that Lin-28 is highly enriched in adult intestinal stem cells in the Drosophila intestine. lin-28 null mutants are homozygous viable but display defects in this population of cells, which fail to undergo a characteristic food-triggered expansion in number and have reduced rates of symmetric division as well as reduced insulin signaling. Immunoprecipitation of Lin-28-bound mRNAs identified Insulin-like Receptor (InR), forced expression of which completely rescues lin-28-associated defects in intestinal stem cell number and division pattern. Furthermore, this stem cell activity of lin-28 is independent of one well-known lin-28 target, the microRNA let-7, which has limited expression in the intestinal epithelium. These results identify Lin-28 as a stem cell intrinsic factor that boosts insulin signaling in intestinal progenitor cells and promotes their symmetric division in response to nutrients, defining a mechanism through which Lin-28 controls the adult stem cell division patterns that underlie tissue homeostasis and regeneration. PMID:26487778

  11. Co-culture with Sertoli cells promotes proliferation and migration of umbilical cord mesenchymal stem cells

    SciTech Connect

    Zhang, Fenxi; Hong, Yan; Liang, Wenmei; Ren, Tongming; Jing, Suhua; Lin, Juntang

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer Co-culture of Sertoli cells (SCs) with human umbilical cord mesenchymal stem cells (UCMSCs). Black-Right-Pointing-Pointer Presence of SCs dramatically increased proliferation and migration of UCMSCs. Black-Right-Pointing-Pointer Presence of SCs stimulated expression of Mdm2, Akt, CDC2, Cyclin D, CXCR4, MAPKs. -- Abstract: Human umbilical cord mesenchymal stem cells (hUCMSCs) have been recently used in transplant therapy. The proliferation and migration of MSCs are the determinants of the efficiency of MSC transplant therapy. Sertoli cells are a kind of 'nurse' cells that support the development of sperm cells. Recent studies show that Sertoli cells promote proliferation of endothelial cells and neural stem cells in co-culture. We hypothesized that co-culture of UCMSCs with Sertoli cells may also promote proliferation and migration of UCMSCs. To examine this hypothesis, we isolated UCMSCs from human cords and Sertoli cells from mouse testes, and co-cultured them using a Transwell system. We found that UCMSCs exhibited strong proliferation ability and potential to differentiate to other cell lineages such as osteocytes and adipocytes. The presence of Sertoli cells in co-culture significantly enhanced the proliferation and migration potential of UCMSCs (P < 0.01). Moreover, these phenotypic changes were accompanied with upregulation of multiple genes involved in cell proliferation and migration including phospho-Akt, Mdm2, phospho-CDC2, Cyclin D1, Cyclin D3 as well as CXCR4, phospho-p44 MAPK and phospho-p38 MAPK. These findings indicate that Sertoli cells boost UCMSC proliferation and migration potential.

  12. Co-transplantation of Hematopoietic Stem Cells and Cxcr4 Gene-Transduced Mesenchymal Stem Cells Promotes Hematopoiesis.

    PubMed

    Chen, Wei; Li, Miao; Su, Guizhen; Zang, Yu; Yan, Zhiling; Cheng, Hai; Pan, Bin; Cao, Jiang; Wu, Qingyun; Zhao, Kai; Zhu, Feng; Zeng, Lingyu; Li, Zhenyu; Xu, Kailin

    2015-04-01

    Mesenchymal stem cells (MSCs) are a promising candidate for cellular therapies. Co-transplantation of MSCs and hematopoietic stem cells (HSCs) promotes successful engraftment and improves hematopoietic recovery. In this study, the effects of co-transplantation of HSCs and mouse bone marrow (BM)-derived MSCs overexpressing CXCR4 (CXCR4-MSC) on CXCR4-MSC homing capacity and the reconstitution potential in lethally irradiated mice were evaluated. Recovery of donor-derived peripheral blood leukocytes and platelets was accelerated when CXCR4-MSCs were co-transplanted with BM cells. The frequency of c-kit(+)Sca(+)Lin(-) HSCs was higher in recipient BM following co-transplantation of CXCR4-MSCs compared with the EGFP-MSC control and the BMT only groups. Surprisingly, the rate of early engraftment of donor-derived BM cells in recipients co-transplanted with CXCR4-MSCs was slightly lower than in the absence of MSCs on day 7. Moreover, co-transplantation of CXCR4-MSCs regulated the balance of T helper cells subsets. Hematopoietic tissue reconstitution was evaluated by histopathological analysis of BM and spleen. Co-transplantation of CXCR4-MSCs was shown to promote the recovery of hematopoietic organs. These findings indicate that co-transplantation of CXCR4-MSCs promotes the early phase of hematopoietic recovery and sustained hematopoiesis. PMID:25391891

  13. Luminal Microbes Promote Monocyte–Stem Cell Interactions Across a Healthy Colonic Epithelium

    PubMed Central

    Skoczek, Dagmara A.; Walczysko, Petr; Horn, Nikki; Parris, Alyson; Clare, Simon; Williams, Mark R.

    2014-01-01

    The intestinal epithelium forms a vital barrier between luminal microbes and the underlying mucosal immune system. Epithelial barrier function is maintained by continuous renewal of the epithelium and is pivotal for gut homeostasis. Breaching of the barrier causes mobilization of immune cells to promote epithelial restitution. However, it is not known whether microbes at the luminal surface of a healthy epithelial barrier influence immune cell mobilization to modulate tissue homeostasis. Using a mouse colonic mucosal explant model, we demonstrate that close proximity of luminal microbes to a healthy, intact epithelium results in rapid mucus secretion and movement of Ly6C+7/4+ monocytes closer to epithelial stem cells. These early events are driven by the epithelial MyD88-signaling pathway and result in increased crypt cell proliferation and intestinal stem cell number. Over time, stem cell number and monocyte–crypt stem cell juxtapositioning return to homeostatic levels observed in vivo. We also demonstrate that reduced numbers of tissue Ly6C+ monocytes can suppress Lgr5EGFP+ stem cell expression in vivo and abrogate the response to luminal microbes ex vivo. The functional link between monocyte recruitment and increased crypt cell proliferation was further confirmed using a crypt–monocyte coculture model. This work demonstrates that the healthy gut epithelium mediates communication between luminal bacteria and monocytes, and monocytes can modulate crypt stem cell number and promote crypt cell proliferation to help maintain gut homeostasis. PMID:24907348

  14. Silver nanoparticles promote osteogenic differentiation of human urine-derived stem cells at noncytotoxic concentrations

    PubMed Central

    Qin, Hui; Zhu, Chen; An, Zhiquan; Jiang, Yao; Zhao, Yaochao; Wang, Jiaxin; Liu, Xin; Hui, Bing; Zhang, Xianlong; Wang, Yang

    2014-01-01

    In tissue engineering, urine-derived stem cells are ideal seed cells and silver nanoparticles (AgNPs) are perfect antimicrobial agents. Due to a distinct lack of information on the effects of AgNPs on urine-derived stem cells, a study was conducted to evaluate the effects of silver ions and AgNPs upon the cytotoxicity and osteogenic differentiation of urine-derived stem cells. Initially, AgNPs or AgNO3 were exposed to urine-derived stem cells for 24 hours. Cytotoxicity was measured using the Cell Counting kit-8 (CCK-8) test. The effects of AgNPs or AgNO3 at the maximum safety concentration determined by the CCK-8 test on osteogenic differentiation of urine-derived stem cells were assessed by alkaline phosphatase activity, Alizarin Red S staining, and the quantitative reverse transcription polymerase chain reaction. Lastly, the effects of AgNPs or AgNO3 on “urine-derived stem cell actin cytoskeleton organization” and RhoA activity were assessed by rhodamine-phalloidin staining and Western blotting. Concentration-dependent toxicity was observed starting at an AgNO3 concentration of 2 μg/mL and at an AgNP concentration of 4 μg/mL. At these concentrations, AgNPs were observed to promote osteogenic differentiation of urine-derived stem cells, induce actin polymerization and increase cytoskeletal tension, and activate RhoA; AgNO3 had no such effects. In conclusion, AgNPs can promote osteogenic differentiation of urine-derived stem cells at a suitable concentration, independently of silver ions, and are suitable for incorporation into tissue-engineered scaffolds that utilize urine-derived stem cells as seed cells. PMID:24899804

  15. Agonism of Wnt/β-catenin signaling promotes mesenchymal stem cell (MSC) expansion

    PubMed Central

    Hoffman, Michael D.; Benoit, Danielle S.W.

    2014-01-01

    Promoting mesenchymal stem cell (MSC) proliferation has numerous applications in stem cell therapies, particularly in the area of regenerative medicine. In order for cell-based regenerative approaches to be realized, MSC proliferation must be achieved in a controlled manner without compromising stem cell differentiation capacities. Here we demonstrate that 6-bromoindirubin-3’-oxime (BIO) increases MSC β-catenin activity 106-fold and stem cell-associated gene expression ~33-fold respectively over untreated controls. Subsequently, BIO treatment increases MSC populations 1.8-fold in typical 2D culture conditions, as well as 1.3-fold when encapsulated within hydrogels compared to untreated cells. Furthermore, we demonstrate that BIO treatment does not reduce MSC multipotency, where MSCs maintain their ability to differentiate into osteoblasts, chondrocytes, and adipocytes using standard conditions. Taken together, our results demonstrate BIOs potential utility as a proliferative agent for cell transplantation and tissue regeneration. PMID:23554411

  16. Endothelial cells mitigate DNA damage and promote the regeneration of hematopoietic stem cells after radiation injury

    PubMed Central

    Zachman, Derek K.; Leon, Ronald P.; Das, Prerna; Goldman, Devorah C.; Hamlin, Kimberly L.; Guha, Chandan; Fleming, William H.

    2014-01-01

    Endothelial cells (ECs) are an essential component of the hematopoietic microenvironment, which maintains and regulates hematopoietic stem cells (HSCs). Although ECs can support the regeneration of otherwise lethally-irradiated HSCs, the mechanisms are not well understood. To further understand this phenomenon, we studied HSC regeneration from irradiated bone marrow using co-culture with human aortic endothelial cells (HAECs). Co-culture with HAECs induced a 24-fold expansion of long-term HSCs (CD150+, lineagelo, Sca-1+, c-Kit+; CD150+LSK cells) in vitro. These cells gave rise to functional hematopoietic stem and progenitor cells (HSPCs) with colony-forming activity, multilineage reconstitution and serial transplantation potential. Furthermore, HAECs significantly reduced DNA damage in irradiated LSK cells within 24 hours. Remarkably, we were able to delay the exposure of irradiated bone marrow to the regenerative, HAEC-derived signals for up to 48 hours and still rescue functional HSCs. G-CSF is the gold standard for promoting hematopoietic regeneration in vivo. However, when compared to HAECs, in vitro G-CSF treatment promoted lineage differentiation and regenerated 5-fold fewer CD150+LSK cells. Together, our results show that HAECs are powerful, direct mitigators of HSC injury and DNA damage. Identification of the HAEC-derived factors that rescue HSCs may lead to improved therapies for hematopoietic regeneration after radiation injury. PMID:23939266

  17. Bidirectional Promoter Engineering for Single Cell MicroRNA Sensors in Embryonic Stem Cells

    PubMed Central

    Sladitschek, Hanna L.

    2016-01-01

    MicroRNAs have emerged as important markers and regulators of cell identity. Precise measurements of cellular miRNA levels rely traditionally on RNA extraction and thus do not allow to follow miRNA expression dynamics at the level of single cells. Non-invasive miRNA sensors present an ideal solution but they critically depend on the performance of suitable ubiquitous promoters that reliably drive expression both in pluripotent and differentiated cell types. Here we describe the engineering of bidirectional promoters that drive the expression of precise ratiometric fluorescent miRNA sensors in single mouse embryonic stem cells (mESCs) and their differentiated derivatives. These promoters are based on combinations of the widely used CAG, EF1α and PGK promoters as well as the CMV and PGK enhancers. miR-142-3p, which is known to be bimodally expressed in mESCs, served as a model miRNA to gauge the precision of the sensors. The performance of the resulting miRNA sensors was assessed by flow cytometry in single stable transgenic mESCs undergoing self-renewal or differentiation. EF1α promoters arranged back-to-back failed to drive the robustly correlated expression of two transgenes. Back-to-back PGK promoters were shut down during mESC differentiation. However, we found that a back-to-back arrangement of CAG promoters with four CMV enhancers provided both robust expression in mESCs undergoing differentiation and the best signal-to-noise for measurement of miRNA activity in single cells among all the sensors we tested. Such a bidirectional promoter is therefore particularly well suited to study the dynamics of miRNA expression during cell fate transitions at the single cell level. PMID:27152616

  18. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

    PubMed Central

    Xiong, Liu-lin; Chen, Zhi-wei; Wang, Ting-hua

    2016-01-01

    Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 μg/L) to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews. PMID:27212919

  19. Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews.

    PubMed

    Xiong, Liu-Lin; Chen, Zhi-Wei; Wang, Ting-Hua

    2016-04-01

    Neural stem cells promote neuronal regeneration and repair of brain tissue after injury, but have limited resources and proliferative ability in vivo. We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews, a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research. We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38, and added nerve growth factor (100 μg/L) to the culture medium. Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls. After 3 days, fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells. These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews. PMID:27212919

  20. Electrochemically Preadsorbed Collagen Promotes Adult Human Mesenchymal Stem Cell Adhesion.

    PubMed

    Benavidez, Tomás E; Wechsler, Marissa E; Farrer, Madeleine M; Bizios, Rena; Garcia, Carlos D

    2016-01-01

    The present article reports on the effect of electric potential on the adsorption of collagen type I (the most abundant component of the organic phase of bone) onto optically transparent carbon electrodes (OTCE) and its mediation on subsequent adhesion of adult, human, mesenchymal stem cells (hMSCs). For this purpose, adsorption of collagen type I was investigated as a function of the protein concentration (0.01, 0.1, and 0.25 mg/mL) and applied potential (open circuit potential [OCP; control], +400, +800, and +1500 mV). The resulting substrate surfaces were characterized using spectroscopic ellipsometry, atomic force microscopy, and cyclic voltammetry. Adsorption of collagen type I onto OTCE was affected by the potential applied to the sorbent surface and the concentration of protein. The higher the applied potential and protein concentration, the higher the adsorbed amount (Γcollagen). It was also observed that the application of potential values higher than +800 mV resulted in the oxidation of the adsorbed protein. Subsequent adhesion of hMSCs on the OTCEs (precoated with the collagen type I films) under standard cell culture conditions for 2 h was affected by the extent of collagen preadsorbed onto the OTCE substrates. Specifically, enhanced hMSCs adhesion was observed when the Γcollagen was the highest. When the collagen type I was oxidized (under applied potential equal to +1500 mV), however, hMSCs adhesion was decreased. These results provide the first correlation between the effects of electric potential on protein adsorption and subsequent modulation of anchorage-dependent cell adhesion. PMID:26549607

  1. CD73-mediated adenosine production promotes stem cell-like properties in mouse Tc17 cells.

    PubMed

    Flores-Santibáñez, Felipe; Fernández, Dominique; Meza, Daniel; Tejón, Gabriela; Vargas, Leonardo; Varela-Nallar, Lorena; Arredondo, Sebastián; Guixé, Victoria; Rosemblatt, Mario; Bono, María Rosa; Sauma, Daniela

    2015-12-01

    The CD73 ectonucleotidase catalyses the hydrolysis of AMP to adenosine, an immunosuppressive molecule. Recent evidence has demonstrated that this ectonucleotidase is up-regulated in T helper type 17 cells when generated in the presence of transforming growth factor-β (TGF-β), and hence CD73 expression is related to the acquisition of immunosuppressive potential by these cells. TGF-β is also able to induce CD73 expression in CD8(+) T cells but the function of this ectonucleotidase in CD8(+) T cells is still unknown. Here, we show that Tc17 cells present high levels of the CD73 ectonucleotidase and produce adenosine; however, they do not suppress the proliferation of CD4(+) T cells. Interestingly, we report that adenosine signalling through A2A receptor favours interleukin-17 production and the expression of stem cell-associated transcription factors such as tcf-7 and lef-1 but restrains the acquisition of Tc1-related effector molecules such as interferon-γ and Granzyme B by Tc17 cells. Within the tumour microenvironment, CD73 is highly expressed in CD62L(+) CD127(+) CD8(+) T cells (memory T cells) and is down-regulated in GZMB(+) KLRG1(+) CD8(+) T cells (terminally differentiated T cells), demonstrating that CD73 is expressed in memory/naive cells and is down-regulated during differentiation. These data reveal a novel function of CD73 ectonucleotidase in arresting CD8(+) T-cell differentiation and support the idea that CD73-driven adenosine production by Tc17 cells may promote stem cell-like properties in Tc17 cells. PMID:26331349

  2. Mesenchymal stem cells derived from low risk acute lymphoblastic leukemia patients promote NK cell antitumor activity.

    PubMed

    Entrena, Ana; Varas, Alberto; Vázquez, Miriam; Melen, Gustavo J; Fernández-Sevilla, Lidia M; García-Castro, Javier; Ramírez, Manuel; Zapata, Agustín G; Vicente, Ángeles

    2015-07-28

    Mesenchymal stem cells (MSCs) are key components of the bone marrow microenvironment which contribute to the maintenance of the hematopoietic stem cell niche and exert immunoregulatory functions in innate and adaptive immunity. We analyze the immunobiology of MSCs derived from acute lymphoblastic leukemia (ALL) patients and their impact on NK cell function. In contrast to the inhibitory effects on the immune response exerted by MSCs from healthy donors (Healthy-MSCs), we demonstrate that MSCs derived from low/intermediate risk ALL patients at diagnosis (ALL-MSCs) promote an efficient NK cell response including cytokine production, phenotypic activation and most importantly, cytotoxicity. Longitudinal studies indicate that these immunostimulatory effects of ALL-MSCs are progressively attenuated. Healthy-MSCs adopt ALL-MSC-like immunomodulatory features when exposed to leukemia cells, acquiring the ability to stimulate NK cell antitumor function. The mechanisms underlying to these functional changes of ALL-MSCs include reduced production of soluble inhibitory factors, differential expression of costimulatory and coinhibitory molecules, increased expression of specific TLRs and Notch pathway activation. Collectively our findings indicate that, in response to leukemia cells, ALL-MSCs could mediate a host beneficial immunomodulatory effect by stimulating the antitumor innate immune response. PMID:25917077

  3. EGFR signaling promotes self-renewal through the establishment of cell polarity in Drosophila follicle stem cells.

    PubMed

    Castanieto, Angela; Johnston, Michael J; Nystul, Todd G

    2014-01-01

    Epithelial stem cells divide asymmetrically, such that one daughter replenishes the stem cell pool and the other differentiates. We found that, in the epithelial follicle stem cell (FSC) lineage of the Drosophila ovary, epidermal growth factor receptor (EGFR) signaling functions specifically in the FSCs to promote the unique partially polarized state of the FSC, establish apical-basal polarity throughout the lineage, and promote FSC maintenance in the niche. In addition, we identified a novel connection between EGFR signaling and the cell-polarity regulator liver kinase B1 (LKB1), which indicates that EGFR signals through both the Ras-Raf-MEK-Erk pathway and through the LKB1-AMPK pathway to suppress apical identity. The development of apical-basal polarity is the earliest visible difference between FSCs and their daughters, and our findings demonstrate that the EGFR-mediated regulation of apical-basal polarity is essential for the segregation of stem cell and daughter cell fates. PMID:25437306

  4. CUDR promotes liver cancer stem cell growth through upregulating TERT and C-Myc

    PubMed Central

    Pu, Hu; Zheng, Qidi; Li, Haiyan; Wu, Mengying; An, Jiahui; Gui, Xin; Li, Tianming; Lu, Dongdong

    2015-01-01

    Cancer up-regulated drug resistant (CUDR) is a novel non-coding RNA gene. Herein, we demonstrate excessive CUDR cooperates with excessive CyclinD1 or PTEN depletion to accelerate liver cancer stem cells growth and liver stem cell malignant transformation in vitro and in vivo. Mechanistically, we reveal the decrease of PTEN in cells may lead to increase binding capacity of CUDR to CyclinD1. Therefore, CUDR-CyclinD1 complex loads onto the long noncoding RNA H19 promoter region that may lead to reduce the DNA methylation on H19 promoter region and then to enhance the H19 expression. Strikingly, the overexpression of H19 increases the binding of TERT to TERC and reduces the interplay between TERT with TERRA, thus enhancing the cell telomerase activity and extending the telomere length. On the other hand, insulator CTCF recruits the CUDR-CyclinD1 complx to form the composite CUDR-CyclinD1-insulator CTCF complex which occupancied on the C-myc gene promoter region, increasing the outcome of oncogene C-myc. Ultimately, excessive TERT and C-myc lead to liver cancer stem cell and hepatocyte-like stem cell malignant proliferation. To understand the novel functions of long noncoding RNA CUDR will help in the development of new liver cancer therapeutic and diagnostic approaches. PMID:26513297

  5. IL-6 Secreted from Senescent Mesenchymal Stem Cells Promotes Proliferation and Migration of Breast Cancer Cells

    PubMed Central

    Di, Guo-hu; Liu, Yang; Lu, Ying; Liu, Jin; Wu, Chutse; Duan, Hai-Feng

    2014-01-01

    Human mesenchymal stem cells (hMSCs) are currently investigated for a variety of therapeutic applications. However, MSCs isolated from primary tissue cannot meet clinical grade needs and should be expanded in vitro for several passages. Although hMSCs show low possibility for undergoing oncogenic transformation, they do, similar to other somatic cells, undergo cellular senescence and their therapeutic potential is diminished when cultured in vitro. However, the role of senescent MSCs in tumor progression remains largely elusive. In the current study, by establishing senescent human umbilical cord mesenchymal stem cells (s-UCMSCs) through the replicative senescence model and genotoxic stress induced premature senescence model, we show that s-UCMSCs significantly stimulate proliferation and migration of breast cancer cells in vitro and tumor progression in a co-transplant xenograft mouse model compared with ‘young’ counterparts (defined as MSCs at passage 5, in contrast to senescent MSCs at passage 45). In addition, we identified IL-6, a known pleiotropic cytokine, as a principal mediator for the tumor-promoting activity of s-UCMSCs by induction of STAT3 phosphorylation. Depletion of IL-6 from s-UCMSCs conditioned medium partially abrogated the stimulatory effect of s-UCMSCs on the proliferation and migration of breast tumor cells. PMID:25419563

  6. Cardiac stem cell genetic engineering using the αMHC promoter

    PubMed Central

    Bailey, Brandi; Izarra, Alberto; Alvarez, Roberto; Fischer, Kimberlee M; Cottage, Christopher T; Quijada, Pearl; Díez-Juan, Antonio; Sussman, Mark A

    2010-01-01

    Aims Cardiac stem cells (CSCs) show potential as a cellular therapeutic approach to blunt tissue damage and facilitate reparative and regenerative processes after myocardial infarction. Despite multiple published reports of improvement, functional benefits remain modest using normal stem cells delivered by adoptive transfer into damaged myocardium. The goal of this study is to enhance survival and proliferation of CSCs that have undergone lineage commitment in early phases as evidenced by expression of proteins driven by the α-myosin heavy chain (αMHC) promoter. The early increased expression of survival kinases augments expansion of the cardiogenic CSC pool and subsequent daughter progeny. Materials & methods Normal CSCs engineered with fluorescent reporter protein constructs under control of the αMHC promoter show transgene protein expression, confirming activity of the promoter in CSCs. Cultured CSCs from both nontransgenic and cardiac-specific transgenic mice expressing survival kinases driven by the αMHC promoter were analyzed to characterize transgene expression following treatments to promote differentiation in culture. Results & conclusion Therapeutic genes controlled by the αMHC promoter can be engineered into and expressed in CSCs and cardiomyocyte progeny with the goal of improving the efficacy of cardiac stem cell therapy. PMID:19903002

  7. Sonic hedgehog promotes stem-cell potential of Mueller glia in the mammalian retina

    SciTech Connect

    Wan Jin; Zheng Hua; Xiao Honglei; She Zhenjue; Zhou Guomin

    2007-11-16

    Mueller glia have been demonstrated to display stem-cell properties after retinal damage. Here, we report this potential can be regulated by Sonic hedgehog (Shh) signaling. Shh can stimulate proliferation of Mueller glia through its receptor and target gene expressed on them, furthermore, Shh-treated Mueller glia are induced to dedifferentiate by expressing progenitor-specific markers, and then adopt cell fate of rod photoreceptor. Inhibition of signaling by cyclopamine inhibits proliferation and dedifferentiation. Intraocular injection of Shh promotes Mueller glia activation in the photoreceptor-damaged retina, Shh also enhances neurogenic potential by producing more rhodopsin-positive photoreceptors from Mueller glia-derived cells. Together, these results provide evidences that Mueller glia act as potential stem cells in mammalian retina, Shh may have therapeutic effects on these cells for promoting the regeneration of retinal neurons.

  8. Combined MSC-Secreted Factors and Neural Stem Cell Transplantation Promote Functional Recovery of PD Rats.

    PubMed

    Yao, Yuan; Huang, Chen; Gu, Ping; Wen, Tieqiao

    2016-01-01

    Stem cell transplantation has enormous potential for the treatment of neurodegenerative disorders like Parkinson's disease (PD). Mesenchymal stem cells (MSCs) have attracted much attention because they can secrete a wide variety of cellular factors that promote cell growth. In this study, we prepared a conditioned medium (CM) using lyophilized MSC culture medium that contained the secretome of MSCs and applied this CM to the culture of neural stem cells (CM-NSCs) for the transplantation of PD model rats. Quantitative real-time PCR, Western blot, and immunocytochemistry were used to identify cell differentiation and expression of dopaminergic neuron-specific genes in vitro. Behavioral tests including rotational behavior and MWM training tests were also performed to assess the recovery. Our results indicated that combined treatment of CM and neural stem cell transplantation can significantly reduce apomorphine-induced rotational asymmetry and improve spatial learning ability. The CM-NSCs were able to differentiate into dopaminergic neurons in the ventral tegmental area (VTA) and medial forebrain bundle (MFB), and migrated around the lesion site. They showed a higher activity than untreated NSCs in cell survival, migration, and behavior improvement in the dopa-deficit rat model. These findings suggest that the neural stem cells treated with conditioned medium possess a great potential as a graft candidate for the treatment of Parkinson's disease. PMID:26607204

  9. WNT5A promotes stemness characteristics in nasopharyngeal carcinoma cells leading to metastasis and tumorigenesis.

    PubMed

    Qin, Li; Yin, Yan-Tao; Zheng, Fang-Jing; Peng, Li-Xia; Yang, Chang-Fu; Bao, Ying-Na; Liang, Ying-Ying; Li, Xin-Jian; Xiang, Yan-Qun; Sun, Rui; Li, An-Hua; Zou, Ru-Hai; Pei, Xiao-Qing; Huang, Bi-Jun; Kang, Tie-Bang; Liao, Duan-Fang; Zeng, Yi-Xin; Williams, Bart O; Qian, Chao-Nan

    2015-04-30

    Nasopharyngeal carcinoma (NPC) has the highest metastasis rate among head and neck cancers with unclear mechanism. WNT5A belongs to the WNT family of cysteine-rich secreted glycoproteins. Our previous high-throughput gene expression profiling revealed that WNT5A was up-regulated in highly metastatic cells. In the present study, we first confirmed the elevated expression of WNT5A in metastatic NPC tissues at both the mRNA and protein levels. We then found that WNT5A promoted epithelial-mesenchymal transition (EMT) in NPC cells, induced the accumulation of CD24-CD44+ cells and side population, which are believed to be cancer stem cell characteristics. Moreover, WNT5A promoted the migration and invasion of NPC cells in vitro, while in vivo treatment with recombinant WNT5A promoted lung metastasis. Knocking down WNT5A diminished NPC tumorigenesis in vivo. When elevated expression of WNT5A coincided with the elevated expression of vimentin in the primary NPC, the patients had a poorer prognosis. Among major signaling pathways, protein kinase C (PKC) signaling was activated by WNT5A in NPC cells. A positive feedback loop between WNT5A and phospho-PKC to promote EMT was also revealed. Taken together, these data suggest that WNT5A is an important molecule in promoting stem cell characteristics in NPC, leading to tumorigenesis and metastasis. PMID:25823923

  10. Hypoxia Promotes the Inflammatory Response and Stemness Features in Visceral Fat Stem Cells From Obese Subjects.

    PubMed

    Petrangeli, Elisa; Coroniti, Giuseppe; Brini, Anna T; de Girolamo, Laura; Stanco, Deborah; Niada, Stefania; Silecchia, Gianfranco; Morgante, Emanuela; Lubrano, Carla; Russo, Matteo A; Salvatori, Luisa

    2016-03-01

    Low-grade chronic inflammation is a salient feature of obesity and many associated disorders. This condition frequently occurs in central obesity and is connected to alterations of the visceral adipose tissue (AT) microenvironment. Understanding how obesity is related to inflammation may allow the development of therapeutics aimed at improving metabolic parameters in obese patients. To achieve this aim, we compared the features of two subpopulations of adipose-derived stem cells (ASC) isolated from both subcutaneous and visceral AT of obese patients with the features of two subpopulations of ASC from the same isolation sites of non-obese individuals. In particular, the behavior of ASC of obese versus non-obese subjects during hypoxia, which occurs in obese AT and is an inducer of the inflammatory response, was evaluated. Obesity deeply influenced ASC from visceral AT (obV-ASC); these cells appeared to exhibit clearly distinguishable morphology and ultrastructure as well as reduced proliferation, clonogenicity and expression of stemness, differentiation and inflammation-related genes. These cells also exhibited a deregulated response to hypoxia, which induced strong tissue-specific NF-kB activation and an NF-kB-mediated increase in inflammatory and fibrogenic responses. Moreover, obV-ASC, which showed a less stem-like phenotype, recovered stemness features after hypoxia. Our findings demonstrated the peculiar behavior of obV-ASC, their influence on the obese visceral AT microenvironment and the therapeutic potential of NF-kB inhibitors. These novel findings suggest that the deregulated hyper-responsiveness to hypoxic stimulus of ASC from visceral AT of obese subjects may contribute via paracrine mechanisms to low-grade chronic inflammation, which has been implicated in obesity-related morbidity. PMID:26224080

  11. Analysis of Different Promoter Systems for Efficient Transgene Expression in Mouse Embryonic Stem Cell Lines

    PubMed Central

    Chung, Sangmi; Andersson, Therese; Sonntag, Kai-C.; Björklund, Lars; Isacson, Ole; Kim, Kwang-Soo

    2008-01-01

    Mouse embryonic stem (ES) cells are derived from the inner cell mass of the preimplantation embryo and have the developmental capacity to generate all cell types of the body. Combined with efficient genetic manipulation and in vitro differentiation procedures, ES cells are a useful system for the molecular analysis of developmental pathways. We analyzed and compared the transcriptional activities of a cellular polypeptide chain elongation factor 1 alpha (EF), a cellular-virus hybrid (cytomegalo-virus [CMV] immediate early enhancer fused to chicken β-actin [CBA]), and a viral CMV promoter system in two ES cell lines. When transiently transfected, the EF and CBA promoters robustly drove reporter gene expression, while the CMV promoter was inactive. We also demonstrated that the EF and CBA promoters effectively drove gene expression in different stages of cell development: naïve ES cells, embryoid bodies (EBs), and neuronal precursor cells. In contrast, the CMV promoter did not have transcriptional activity in either ES cells or EB but had significant activity once ES cells differentiated into neuronal precursors. Our data show that individual promoters have different abilities to express reporter gene expression in the ES and other cell types tested. PMID:11897870

  12. Leukemia cell microvesicles promote survival in umbilical cord blood hematopoietic stem cells

    PubMed Central

    Razmkhah, Farnaz; Soleimani, Masoud; Mehrabani, Davood; Karimi, Mohammad Hossein; Kafi-abad, Sedigheh Amini

    2015-01-01

    Microvesicles can transfer their contents, proteins and RNA, to target cells and thereby transform them. This may induce apoptosis or survival depending on cell origin and the target cell. In this study, we investigate the effect of leukemic cell microvesicles on umbilical cord blood hematopoietic stem cells to seek evidence of apoptosis or cell survival. Microvesicles were isolated from both healthy donor bone marrow samples and Jurkat cells by ultra-centrifugation and were added to hematopoietic stem cells sorted from umbilical cord blood samples by magnetic associated cell sorting (MACS) technique. After 7 days, cell count, cell viability, flow cytometry analysis for hematopoietic stem cell markers and qPCR for P53 gene expression were performed. The results showed higher cell number, higher cell viability rate and lower P53 gene expression in leukemia group in comparison with normal and control groups. Also, CD34 expression as the most important hematopoietic stem cell marker, did not change during the treatment and lineage differentiation was not observed. In conclusion, this study showed anti-apoptotic effect of leukemia cell derived microvesicles on umbilical cord blood hematopoietic stem cells. PMID:26862318

  13. ISG15 predicts poor prognosis and promotes cancer stem cell phenotype in nasopharyngeal carcinoma

    PubMed Central

    Han, Ping; Wang, Hong-Bo; Liang, Fa-Ya; Feng, Guo-Kai; Zhou, Ai-Jun; Cai, Mu-Yan; Zhong, Qian; Zeng, Mu-Sheng; Huang, Xiao-Ming

    2016-01-01

    Interferon-stimulated gene 15 (ISG15), the first identified ubiquitin-like protein, is known for its anti-viral capacity. However, its role in tumorigenesis remains controversial. Here, using RNA-seq profiling analysis, we identified ISG15 as a differentially expressed gene in nasopharyngeal carcinoma (NPC) and validated its overexpression in NPC samples and cells. High ISG15 levels in NPC tissues were correlated with more frequent local recurrence and shorter overall survival and disease-free survival. ISG15 overexpression promoted a cancer stem cell phenotype in NPC cells, including increased colony and tumorsphere formation abilities, pluripotency-associated genes expression, and in vivo tumorigenicity. By contrast, knockdown of ISG15 attenuated stemness characteristics in NPC cells. Furthermore, overexpression of ISG15 increased NPC cell resistance to radiation and cisplatin (DDP) treatment. Our study demonstrates a protumor role of ISG15, and suggests that ISG15 is a prognostic predictor and a potential therapeutic target for NPC. PMID:26919245

  14. Spermidine Promotes Human Hair Growth and Is a Novel Modulator of Human Epithelial Stem Cell Functions

    PubMed Central

    Bíró, Tamás; Abu Bakar, Mohd Hilmi; Sugawara, Koji; Philpott, Michael P.; Harrison, Wesley; Pietilä, Marko; Paus, Ralf

    2011-01-01

    Background Rapidly regenerating tissues need sufficient polyamine synthesis. Since the hair follicle (HF) is a highly proliferative mini-organ, polyamines may also be important for normal hair growth. However, the role of polyamines in human HF biology and their effect on HF epithelial stem cells in situ remains largely unknown. Methods and Findings We have studied the effects of the prototypic polyamine, spermidine (0.1–1 µM), on human scalp HFs and human HF epithelial stem cells in serum-free organ culture. Under these conditions, spermidine promoted hair shaft elongation and prolonged hair growth (anagen). Spermidine also upregulated expression of the epithelial stem cell-associated keratins K15 and K19, and dose-dependently modulated K15 promoter activity in situ and the colony forming efficiency, proliferation and K15 expression of isolated human K15-GFP+ cells in vitro. Inhibiting the rate-limiting enzyme of polyamine synthesis, ornithine decarboyxlase (ODC), downregulated intrafollicular K15 expression. In primary human epidermal keratinocytes, spermidine slightly promoted entry into the S/G2-M phases of the cell cycle. By microarray analysis of human HF mRNA extracts, spermidine upregulated several key target genes implicated e.g. in the control of cell adherence and migration (POP3), or endoplasmic reticulum and mitochondrial functions (SYVN1, NACA and SLC25A3). Excess spermidine may restrict further intrafollicular polyamine synthesis by inhibiting ODC gene and protein expression in the HF's companion layer in situ. Conclusions These physiologically and clinically relevant data provide the first direct evidence that spermidine is a potent stimulator of human hair growth and a previously unknown modulator of human epithelial stem cell biology. PMID:21818338

  15. Types of Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... stem cells blog from the International Society for Stem Cell Research. Learn About Stem Cells From Lab to You ...

  16. Mesenchymal Stem Cell-Derived Extracellular Vesicles Promote Angiogenesis: Potencial Clinical Application

    PubMed Central

    Merino-González, Consuelo; Zuñiga, Felipe A.; Escudero, Carlos; Ormazabal, Valeska; Reyes, Camila; Nova-Lamperti, Estefanía; Salomón, Carlos; Aguayo, Claudio

    2016-01-01

    Mesenchymal stem cells (MSCs) are adult multipotent stem cells that are able to differentiate into multiple specialized cell types including osteocytes, adipocytes, and chondrocytes. MSCs exert different functions in the body and have recently been predicted to have a major clinical/therapeutic potential. However, the mechanisms of self-renewal and tissue regeneration are not completely understood. It has been shown that the biological effect depends mainly on its paracrine action. Furthermore, it has been reported that the secretion of soluble factors and the release of extracellular vesicles, such as exosomes, could mediate the cellular communication to induce cell-differentiation/self-renewal. This review provides an overview of MSC-derived exosomes in promoting angiogenicity and of the clinical relevance in a therapeutic approach. PMID:26903875

  17. Niche signaling promotes stem cell survival in the Drosophila testis via the Jak-STAT target DIAP1

    PubMed Central

    Hasan, Salman; Hétié, Phylis; Matunis, Erika L.

    2015-01-01

    Tissue-specific stem cells are thought to resist environmental insults better than their differentiating progeny, but this resistance varies from one tissue to another, and the underlying mechanisms are not well-understood. Here, we use the Drosophila testis as a model system to study the regulation of cell death within an intact niche. This niche contains sperm-producing germline stem cells (GSCs) and accompanying somatic cyst stem cells (or CySCs). Although many signals are known to promote stem cell self-renewal in this tissue, including the highly conserved JAK-STAT pathway, the response of these stem cells to potential death-inducing signals, and factors promoting stem cell survival, have not been characterized. Here we find that both GSCs and CySCs resist cell death better than their differentiating progeny, under normal laboratory conditions and in response to potential death-inducing stimuli such as irradiation or starvation. To ask what might be promoting stem cell survival, we characterized the role of the anti-apoptotic gene Drosophila inhibitor of apoptosis 1 (diap1) in testis stem cells. DIAP1 protein is enriched in the GSCs and CySCs and is a Jak-STAT target. diap1 is necessary for survival of both GSCs and CySCs, and ectopic up-regulation of DIAP1 in somatic cyst cells is sufficient to non-autonomously rescue stress-induced cell death in adjacent differentiating germ cells (spermatogonia). Altogether, our results show that niche signals can promote stem cell survival by up-regulation of highly conserved anti-apoptotic proteins, and suggest that this strategy may underlie the ability of stem cells to resist death more generally. PMID:25941003

  18. Angiogenin Promotes Hematopoietic Regeneration by Dichotomously Regulating Quiescence of Stem and Progenitor Cells.

    PubMed

    Goncalves, Kevin A; Silberstein, Lev; Li, Shuping; Severe, Nicolas; Hu, Miaofen G; Yang, Hailing; Scadden, David T; Hu, Guo-Fu

    2016-08-11

    Regulation of stem and progenitor cell populations is critical in the development, maintenance, and regeneration of tissues. Here, we define a novel mechanism by which a niche-secreted RNase, angiogenin (ANG), distinctively alters the functional characteristics of primitive hematopoietic stem/progenitor cells (HSPCs) compared with lineage-committed myeloid-restricted progenitor (MyePro) cells. Specifically, ANG reduces the proliferative capacity of HSPC while simultaneously increasing proliferation of MyePro cells. Mechanistically, ANG induces cell-type-specific RNA-processing events: tRNA-derived stress-induced small RNA (tiRNA) generation in HSPCs and rRNA induction in MyePro cells, leading to respective reduction and increase in protein synthesis. Recombinant ANG protein improves survival of irradiated animals and enhances hematopoietic regeneration of mouse and human HSPCs in transplantation. Thus, ANG plays a non-cell-autonomous role in regulation of hematopoiesis by simultaneously preserving HSPC stemness and promoting MyePro proliferation. These cell-type-specific functions of ANG suggest considerable therapeutic potential. PMID:27518564

  19. Hypoxia promotes thyroid differentiation of native murine induced pluripotent stem cells.

    PubMed

    Yang, Yipeng; Lu, Yunshu; Chen, Tong; Zhang, Shenglai; Chu, Bingfeng; Gong, Yurong; Zhao, Weixin; Zhu, Jian; Liu, Yingbin

    2016-01-01

    Hypothyroidism is a very common hormonal deficiency and the stem cell technology which developed in the recent years may offer a therapeutic strategy for treating this disorder. Hypoxia has been demonstrated to play an important role in embryonic formation and development and to modulate stem cell differentiation. However, the influence of oxygen tension on thyroid differentiation has not been studied. In this study, we used murine induced pluripotent stem (iPS) cells for thyroid cell differentiation under normoxic and hypoxic conditions and compared differentiation efficiency in morphology, function, gene and protein expression under both conditions. We found that hypoxia promoted adhesion and outgrowth of embryoid bodies (EBs) derived from murine iPS cells. Expression of endodermal markers (Foxa2 and Gata4) and thyroid transcription factors (Pax8 and Nkx2.1) was increased by hypoxia at both gene and protein levels during early-mid differentiation stages (p<0.05). And so were the thyroid specific markers NIS and TSHR at the end of the experiment (p<0.05). In addition, functional iodide uptake by differentiated cells was also increased after hypoxia. Thyroid differentiation from iPS cells is enhanced under hypoxia and this may involve hypoxia inducible factors (HIFs) and their downstream gene FGF2. Our data offer a foundation for understanding thyroid development and provide a potentially more efficient way to use cell therapy for treating thyroid deficiency. PMID:27389981

  20. The senescent microenvironment promotes the emergence of heterogeneous cancer stem-like cells.

    PubMed

    Castro-Vega, Luis Jaime; Jouravleva, Karina; Ortiz-Montero, Paola; Liu, Win-Yan; Galeano, Jorge Luis; Romero, Martha; Popova, Tatiana; Bacchetti, Silvia; Vernot, Jean Paul; Londoño-Vallejo, Arturo

    2015-10-01

    There is a well-established association between aging and the onset of metastasis. Although the mechanisms through which age impinges upon the malignant phenotype remain uncharacterized, the role of a senescent microenvironment has been emphasized. We reported previously that human epithelial cells that undergo telomere-driven chromosome instability (T-CIN) display global microRNA (miR) deregulation and develop migration and invasion capacities. Here, we show that post-crisis cells are not able to form tumors unless a senescent microenvironment is provided. The characterization of cell lines established from such tumors revealed that these cells have acquired cell autonomous tumorigenicity, giving rise to heterogeneous tumors. Further experiments demonstrate that explanted cells, while displaying differences in cell differentiation markers, are all endowed of enhanced stem cell properties including self-renewal and multilineage differentiation capacity. Treatments of T-CIN+ cells with senescence-conditioned media induce sphere formation exclusively in cells with senescence-associated tumorigenicity, a capacity that depends on miR-145 repression. These results indicate that the senescent microenvironment, while promoting further transdifferentiations in cells with genome instability, is able to propel the progression of premalignant cells towards a malignant, cell stem-like state. PMID:26168819

  1. Promotion of haematopoietic activity in embryonic stem cells by the aorta-gonad-mesonephros microenvironment

    SciTech Connect

    Krassowska, Anna; Gordon-Keylock, Sabrina; Samuel, Kay; Gilchrist, Derek; Dzierzak, Elaine; Oostendorp, Robert; Forrester, Lesley M. . E-mail: l.forrester@ed.ac.uk; Ansell, John D.

    2006-11-01

    We investigated whether the in vitro differentiation of ES cells into haematopoietic progenitors could be enhanced by exposure to the aorta-gonadal-mesonephros (AGM) microenvironment that is involved in the generation of haematopoietic stem cells (HSC) during embryonic development. We established a co-culture system that combines the requirements for primary organ culture and differentiating ES cells and showed that exposure of differentiating ES cells to the primary AGM region results in a significant increase in the number of ES-derived haematopoietic progenitors. Co-culture of ES cells on the AM20-1B4 stromal cell line derived from the AGM region also increases haematopoietic activity. We conclude that factors promoting the haematopoietic activity of differentiating ES cells present in primary AGM explants are partially retained in the AM20.1B4 stromal cell line and that these factors are likely to be different to those required for adult HSC maintenance.

  2. Transplantation of human amniotic mesenchymal stem cells promotes neurological recovery in an intracerebral hemorrhage rat model.

    PubMed

    Zhou, Honglong; Zhang, Hongri; Yan, Zhongjie; Xu, Ruxiang

    2016-06-24

    Human amniotic membrane mesenchymal stem cells (hAMSCs) have recently been suggested as ideal candidate stem cells for cell-based therapy. Many studies have reported the therapeutic effects of hAMSCs in numerous disease models. However, no studies have used hAMSCs to treat intracerebral hemorrhage (ICH). In the present study, we examined the therapeutic potential of hAMSCs in a rat model of ICH, and characterized the possible mechanisms of action. Adult male Wistar rats were subjected to ICH by intrastriatal injection of VII collagenase, and then were intracerebrally administered hAMSCs, fibroblasts, or phosphate-buffered saline (PBS) at 24 h after ICH. Compared with the fibroblasts and the PBS control, hAMSCs treatment significantly promoted neurological recovery, and reduced the numbers of ED1(+) activated microglia, as well as myeloperoxidase (MPO(+)), and caspase-3(+) cells in the brain injury model. In addition, hAMSCs treatment significantly increased the expression of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) in the injured brain, and promoted neurogenesis and angiogenesis, compared with the fibroblasts and the PBS control. The transplanted hAMSCs survived for at least 27 days and were negative for β-tubulin III and glial fibrillary acidic protein (GFAP). Taken together, the results suggest that hAMSCs treatment significantly promotes neurological recovery in rats after ICH. The mechanism of action could be mediated by inhibition of inflammation and apoptosis, increasing neurotrophic factor expression, and promotion of neurogenesis and angiogenesis. Thus, hAMSCs are candidate stem cells for the treatment of ICH. PMID:27188654

  3. Collagen Promotes Higher Adhesion, Survival and Proliferation of Mesenchymal Stem Cells

    PubMed Central

    Somaiah, Chinnapaka; Kumar, Atul; Mawrie, Darilang; Sharma, Amit; Patil, Suraj Dasharath; Bhattacharyya, Jina; Swaminathan, Rajaram; Jaganathan, Bithiah Grace

    2015-01-01

    Mesenchymal stem cells (MSC) can differentiate into several cell types and are desirable candidates for cell therapy and tissue engineering. However, due to poor cell survival, proliferation and differentiation in the patient, the therapy outcomes have not been satisfactory. Although several studies have been done to understand the conditions that promote proliferation, differentiation and migration of MSC in vitro and in vivo, still there is no clear understanding on the effect of non-cellular bio molecules. Of the many factors that influence the cell behavior, the immediate cell microenvironment plays a major role. In this context, we studied the effect of extracellular matrix (ECM) proteins in controlling cell survival, proliferation, migration and directed MSC differentiation. We found that collagen promoted cell proliferation, cell survival under stress and promoted high cell adhesion to the cell culture surface. Increased osteogenic differentiation accompanied by high active RHOA (Ras homology gene family member A) levels was exhibited by MSC cultured on collagen. In conclusion, our study shows that collagen will be a suitable matrix for large scale production of MSC with high survival rate and to obtain high osteogenic differentiation for therapy. PMID:26661657

  4. Collagen Promotes Higher Adhesion, Survival and Proliferation of Mesenchymal Stem Cells.

    PubMed

    Somaiah, Chinnapaka; Kumar, Atul; Mawrie, Darilang; Sharma, Amit; Patil, Suraj Dasharath; Bhattacharyya, Jina; Swaminathan, Rajaram; Jaganathan, Bithiah Grace

    2015-01-01

    Mesenchymal stem cells (MSC) can differentiate into several cell types and are desirable candidates for cell therapy and tissue engineering. However, due to poor cell survival, proliferation and differentiation in the patient, the therapy outcomes have not been satisfactory. Although several studies have been done to understand the conditions that promote proliferation, differentiation and migration of MSC in vitro and in vivo, still there is no clear understanding on the effect of non-cellular bio molecules. Of the many factors that influence the cell behavior, the immediate cell microenvironment plays a major role. In this context, we studied the effect of extracellular matrix (ECM) proteins in controlling cell survival, proliferation, migration and directed MSC differentiation. We found that collagen promoted cell proliferation, cell survival under stress and promoted high cell adhesion to the cell culture surface. Increased osteogenic differentiation accompanied by high active RHOA (Ras homology gene family member A) levels was exhibited by MSC cultured on collagen. In conclusion, our study shows that collagen will be a suitable matrix for large scale production of MSC with high survival rate and to obtain high osteogenic differentiation for therapy. PMID:26661657

  5. Regulation of c-Myc Expression by Ahnak Promotes Induced Pluripotent Stem Cell Generation.

    PubMed

    Lim, Hee Jung; Kim, Jusong; Park, Chang-Hwan; Lee, Sang A; Lee, Man Ryul; Kim, Kye-Seong; Kim, Jaesang; Bae, Yun Soo

    2016-01-01

    We have previously reported that Ahnak-mediated TGFβ signaling leads to down-regulation of c-Myc expression. Here, we show that inhibition of Ahnak can promote generation of induced pluripotent stem cells (iPSC) via up-regulation of endogenous c-Myc. Consistent with the c-Myc inhibitory role of Ahnak, mouse embryonic fibroblasts from Ahnak-deficient mouse (Ahnak(-/-) MEF) show an increased level of c-Myc expression compared with wild type MEF. Generation of iPSC with just three of the four Yamanaka factors, Oct4, Sox2, and Klf4 (hereafter 3F), was significantly enhanced in Ahnak(-/-) MEF. Similar results were obtained when Ahnak-specific shRNA was applied to wild type MEF. Of note, expressionof Ahnak was significantly induced during the formation of embryoid bodies from embryonic stem cells, suggesting that Ahnak-mediated c-Myc inhibition is involved in embryoid body formation and the initial differentiation of pluripotent stem cells. The iPSC from 3F-infected Ahnak(-/-) MEF cells (Ahnak(-/-)-iPSC-3F) showed expression of all stem cell markers examined and the capability to form three primary germ layers. Moreover, injection of Ahnak(-/-)-iPSC-3F into athymic nude mice led to development of teratoma containing tissues from all three primary germ layers, indicating that iPSC from Ahnak(-/-) MEF are bona fide pluripotent stem cells. Taken together, these data provide evidence for a new role for Ahnak in cell fate determination during development and suggest that manipulation of Ahnak and the associated signaling pathway may provide a means to regulate iPSC generation. PMID:26598518

  6. Exendin-4 promotes proliferation of adipose-derived stem cells through ERK and JNK signaling pathways.

    PubMed

    Zhang, Ying; Chen, Shi; Liu, Baichuan; Zhou, Hao; Hu, Shunyin; Zhou, Ying; Han, Tianwen; Chen, Yundai

    2016-05-01

    Adipose-derived stem cell (ADSC) transplantation has emerged as a potential tool for the treatment of cardiovascular disease. However, with a limited renewal capacity and the need for mass cells during the engraftment, strategies are needed to enhance ADSC proliferative capacity. In this study, we explored the effects of exendin-4 (Ex-4), a glucagon-like peptide-1 analog, on the growth of ADSCs, focusing in particular on c-Jun NH2-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) signaling pathways. Firstly, ADSCs were isolated and cultured in vitro. Then, flow cytometry demonstrated that ADSCs were positive for CD90 and CD29 but negative for CD31, CD34, and CD45. Ex-4 (0-50 nM) treatment increased ADSC proliferation in a dose-dependent manner but had no effects on stem cell markers of ADSCs. Moreover, we found that Ex-4 treatment elevated the phosphorylation levels of the JNK and ERK signaling pathways. Furthermore, utilization of Ex-4 also promoted cyclin D1 and cyclin E protein expression, which was accompanied by more Edu(+) cells and a higher percentage of cells in the S-phase of the cell cycle after Ex-4 treatment. In parallel, the application of inhibitors SP600125 and PD98059, inhibitors of the JNK and ERK signaling pathways, respectively, not only reversed such effects of Ex-4 on JNK and ERK but also resulted in lower percentages of S-phase cells and fewer numbers of Edu(+) cells. In summary, Ex-4 has no effects on stem cell markers in ADSCs but promotes ADSC growth via JNK and ERK signaling pathways. PMID:26932601

  7. A feedback amplification loop between stem cells and their progeny promotes tissue regeneration and tumorigenesis

    PubMed Central

    Chen, Jun; Xu, Na; Huang, Huanwei; Cai, Tao; Xi, Rongwen

    2016-01-01

    Homeostatic renewal of many adult tissues requires balanced self-renewal and differentiation of local stem cells, but the underlying mechanisms are poorly understood. Here we identified a novel feedback mechanism in controlling intestinal regeneration and tumorigenesis in Drosophila. Sox21a, a group B Sox protein, is preferentially expressed in the committed progenitor named enteroblast (EB) to promote enterocyte differentiation. In Sox21a mutants, EBs do not divide, but cannot differentiate properly and have increased expression of mitogens, which then act as paracrine signals to promote intestinal stem cell (ISC) proliferation. This leads to a feedback amplification loop for rapid production of differentiation-defective EBs and tumorigenesis. Notably, in normal intestine following damage, Sox21a is temporally downregulated in EBs to allow the activation of the ISC-EB amplification loop for epithelial repair. We propose that executing a feedback amplification loop between stem cells and their progeny could be a common mechanism underlying tissue regeneration and tumorigenesis. DOI: http://dx.doi.org/10.7554/eLife.14330.001 PMID:27187149

  8. Transplantation of Neural Stem Cells Clonally Derived from Embryonic Stem Cells Promotes Recovery After Murine Spinal Cord Injury

    PubMed Central

    Salewski, Ryan P.; Mitchell, Robert A.; Shen, Carl

    2015-01-01

    The pathology of spinal cord injury (SCI) makes it appropriate for cell-based therapies. Treatments using neural stem cells (NSCs) in animal models of SCI have shown positive outcomes, although uncertainty remains regarding the optimal cell source. Pluripotent cell sources such as embryonic stem cells (ESCs) provide a limitless supply of therapeutic cells. NSCs derived using embryoid bodies (EB) from ESCs have shown tumorigenic potential. Clonal neurosphere generation is an alternative method to generate safer and more clinically relevant NSCs without the use of an EB stage for use in cell-based therapies. We generated clonally derived definitive NSCs (dNSCs) from ESC. These cells were transplanted into a mouse thoracic SCI model. Embryonic stem cell-derived definitive neural stem cell (ES-dNSC)-transplanted mice were compared with controls using behavioral measures and histopathological analysis of tissue. In addition, the role of remyelination in injury recovery was investigated using transmission electron microscopy. The SCI group that received ES-dNSC transplantation showed significant improvements in locomotor function compared with controls in open field and gait analysis. The cell treatment group had a significant enhancement of spared neural tissue. Immunohistological assessments showed that dNSCs differentiated primarily to oligodendrocytes. These cells were shown to express myelin basic protein, associate with axons, and support nodal architecture as well as display proper compact, multilayer myelination in electron microscopic analysis. This study provides strong evidence that dNSCs clonally derived from pluripotent cells using the default pathway of neuralization improve motor function after SCI and enhance sparing of neural tissue, while remaining safe and clinically relevant. PMID:25119334

  9. Stem cells supporting other stem cells

    PubMed Central

    Leatherman, Judith

    2013-01-01

    Adult stem cell therapies are increasingly prevalent for the treatment of damaged or diseased tissues, but most of the improvements observed to date are attributed to the ability of stem cells to produce paracrine factors that have a trophic effect on existing tissue cells, improving their functional capacity. It is now clear that this ability to produce trophic factors is a normal and necessary function for some stem cell populations. In vivo adult stem cells are thought to self-renew due to local signals from the microenvironment where they live, the niche. Several niches have now been identified which harbor multiple stem cell populations. In three of these niches – the Drosophila testis, the bulge of the mammalian hair follicle, and the mammalian bone marrow – one type of stem cell has been found to produce factors that contribute to the maintenance of a second stem cell population in the shared niche. In this review, I will examine the architecture of these three niches and discuss the molecular signals involved. Together, these examples establish a new paradigm for stem cell behavior, that stem cells can promote the maintenance of other stem cells. PMID:24348512

  10. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

    NASA Astrophysics Data System (ADS)

    Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z.; Gimzewski, James K.; Nakano, Atsushi

    2013-04-01

    While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.

  11. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

    PubMed Central

    Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z.; Gimzewski, James K.; Nakano, Atsushi

    2013-01-01

    While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of the matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examined the role of matrix rigidity on the cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using an genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of the already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes. PMID:24311969

  12. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells.

    PubMed

    Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z; Gimzewski, James K; Nakano, Atsushi

    2013-08-01

    While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of the matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examined the role of matrix rigidity on the cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using an genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of the already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes. PMID:24311969

  13. Decellularized Matrix from Tumorigenic Human Mesenchymal Stem Cells Promotes Neovascularization with Galectin-1 Dependent Endothelial Interaction

    PubMed Central

    Burns, Jorge S.; Kristiansen, Malthe; Kristensen, Lars P.; Larsen, Kenneth H.; Nielsen, Maria O.; Christiansen, Helle; Nehlin, Jan; Andersen, Jens S.; Kassem, Moustapha

    2011-01-01

    Background Acquisition of a blood supply is fundamental for extensive tumor growth. We recently described vascular heterogeneity in tumours derived from cell clones of a human mesenchymal stem cell (hMSC) strain (hMSC-TERT20) immortalized by retroviral vector mediated human telomerase (hTERT) gene expression. Histological analysis showed that cells of the most vascularized tumorigenic clone, -BD11 had a pericyte-like alpha smooth muscle actin (ASMA+) and CD146+ positive phenotype. Upon serum withdrawal in culture, -BD11 cells formed cord-like structures mimicking capillary morphogenesis. In contrast, cells of the poorly tumorigenic clone, -BC8 did not stain for ASMA, tumours were less vascularized and serum withdrawal in culture led to cell death. By exploring the heterogeneity in hMSC-TERT20 clones we aimed to understand molecular mechanisms by which mesenchymal stem cells may promote neovascularization. Methodology/Principal Findings Quantitative qRT-PCR analysis revealed similar mRNA levels for genes encoding the angiogenic cytokines VEGF and Angiopoietin-1 in both clones. However, clone-BD11 produced a denser extracellular matrix that supported stable ex vivo capillary morphogenesis of human endothelial cells and promoted in vivo neovascularization. Proteomic characterization of the -BD11 decellularized matrix identified 50 extracellular angiogenic proteins, including galectin-1. siRNA knock down of galectin-1 expression abrogated the ex vivo interaction between decellularized -BD11 matrix and endothelial cells. More stable shRNA knock down of galectin-1 expression did not prevent -BD11 tumorigenesis, but greatly reduced endothelial migration into -BD11 cell xenografts. Conclusions Decellularized hMSC matrix had significant angiogenic potential with at least 50 angiogenic cell surface and extracellular proteins, implicated in attracting endothelial cells, their adhesion and activation to form tubular structures. hMSC -BD11 surface galectin-1 expression was

  14. Adipocytes promote prostate cancer stem cell self-renewal through amplification of the cholecystokinin autocrine loop

    PubMed Central

    Tang, Kai-Dun; Liu, Ji; Jovanovic, Lidija; An, Jiyuan; Hill, Michelle M.; Vela, Ian; Lee, Terence Kin-Wah; Ma, Stephanie; Nelson, Colleen; Russell, Pamela J.; Clements, Judith A.; Ling, Ming-Tat

    2016-01-01

    Obesity has long been linked with prostate cancer progression, although the underlying mechanism is still largely unknown. Here, we report that adipocytes promote the enrichment of prostate cancer stem cells (CSCs) through a vicious cycle of autocrine amplification. In the presence of adipocytes, prostate cancer cells actively secrete the peptide hormone cholecystokinin (CCK), which not only stimulates prostate CSC self-renewal, but also induces cathepsin B (CTSB) production of the adipocytes. In return, CTSB facilitates further CCK secretion by the cancer cells. More importantly, inactivation of CCK receptor not only suppresses CTSB secretion by the adipocytes, but also synergizes the inhibitory effect of CTSB inhibitor on adipocyte-promoted prostate CSC self-renewal. In summary, we have uncovered a novel mechanism underlying the mutual interplay between adipocytes and prostate CSCs, which may help explaining the role of adipocytes in prostate cancer progression and provide opportunities for effective intervention. PMID:26700819

  15. FOXP1 functions as an oncogene in promoting cancer stem cell-like characteristics in ovarian cancer cells.

    PubMed

    Choi, Eun Jung; Seo, Eun Jin; Kim, Dae Kyoung; Lee, Su In; Kwon, Yang Woo; Jang, Il Ho; Kim, Ki-Hyung; Suh, Dong-Soo; Kim, Jae Ho

    2016-01-19

    Ovarian cancer has the highest mortality rate of all gynecological cancers with a high recurrence rate. It is important to understand the nature of recurring cancer cells to terminally eliminate ovarian cancer. The winged helix transcription factor Forkhead box P1 (FOXP1) has been reported to function as either oncogene or tumor-suppressor in various cancers. In the current study, we show that FOXP1 promotes cancer stem cell-like characteristics in ovarian cancer cells. Knockdown of FOXP1 expression in A2780 or SKOV3 ovarian cancer cells decreased spheroid formation, expression of stemness-related genes and epithelial to mesenchymal transition-related genes, cell migration, and resistance to Paclitaxel or Cisplatin treatment, whereas overexpression of FOXP1 in A2780 or SKOV3 ovarian cancer cells increased spheroid formation, expression of stemness-related genes and epithelial to mesenchymal transition-related genes, cell migration, and resistance to Paclitaxel or Cisplatin treatment. In addition, overexpression of FOXP1 increased promoter activity of ABCG2, OCT4, NANOG, and SOX2, among which the increases in ABCG2, OCT4, and SOX2 promoter activity were dependent on the presence of FOXP1-binding site. In xenotransplantation of A2780 ovarian cancer cells into nude mice, knockdown of FOXP1 expression significantly decreased tumor size. These results strongly suggest FOXP1 functions as an oncogene by promoting cancer stem cell-like characteristics in ovarian cancer cells. Targeting FOXP1 may provide a novel therapeutic opportunity for developing a relapse-free treatment for ovarian cancer patients. PMID:26654944

  16. Hepatocellular carcinoma: thyroid hormone promotes tumorigenicity through inducing cancer stem-like cell self-renewal

    PubMed Central

    Wang, Tao; Xia, Lei; Ma, Sicong; Qi, Xingxing; Li, Qigen; Xia, Yun; Tang, Xiaoyin; Cui, Dan; Wang, Zhi; Chi, Jiachang; Li, Ping; Feng, Yu-xiong; Xia, Qiang; Zhai, Bo

    2016-01-01

    Cancer stem-like cells (CSCs) play a key role in maintaining the aggressiveness of hepatocellular carcinoma (HCC), but the cell-biological regulation of CSCs is unclear. In the study, we report that thyroid hormone (TH) promotes cell self-renewal in HCC cells. TH also increases the percentage of CD90 + HCC cells and promotes drug resistance of HCC cells. By analyzing primary human HCC samples, we found that TRα transcript level is significantly elevated in primary liver cancer and portal vein metastatic tumor, compared to that of adjacent normal liver tissue. Knocking down TRα not only inhibits HCC self-renewal in vitro but also suppresses HCC tumor growth in vivo. Interestingly, treatment of TH leads to activation of NF-κB, which is required for the function of TH on inducing HCC cell self-renewal. We also found TRα and p65 cooperatively drive the expression of BMI1 by co-binding to the promoter region of BMI1 gene. In summary, our study uncovers a novel function of TH signaling in regulating the CSCs of HCC, and these findings might be useful for developing novel therapies by targeting TH function in HCC cells. PMID:27174710

  17. Vascular niche promotes hematopoietic multipotent progenitor formation from pluripotent stem cells

    PubMed Central

    Gori, Jennifer L.; Butler, Jason M.; Chan, Yan-Yi; Chandrasekaran, Devikha; Poulos, Michael G.; Ginsberg, Michael; Nolan, Daniel J.; Elemento, Olivier; Wood, Brent L.; Adair, Jennifer E.; Rafii, Shahin; Kiem, Hans-Peter

    2015-01-01

    Pluripotent stem cells (PSCs) represent an alternative hematopoietic stem cell (HSC) source for treating hematopoietic disease. The limited engraftment of human PSC–derived (hPSC-derived) multipotent progenitor cells (MPP) has hampered the clinical application of these cells and suggests that MPP require additional cues for definitive hematopoiesis. We hypothesized that the presence of a vascular niche that produces Notch ligands jagged-1 (JAG1) and delta-like ligand-4 (DLL4) drives definitive hematopoiesis. We differentiated hes2 human embryonic stem cells (hESC) and Macaca nemestrina–induced PSC (iPSC) line-7 with cytokines in the presence or absence of endothelial cells (ECs) that express JAG1 and DLL4. Cells cocultured with ECs generated substantially more CD34+CD45+ hematopoietic progenitors compared with cells cocultured without ECs or with ECs lacking JAG1 or DLL4. EC-induced cells exhibited Notch activation and expressed HSC-specific Notch targets RUNX1 and GATA2. EC-induced PSC-MPP engrafted at a markedly higher level in NOD/SCID/IL-2 receptor γ chain–null (NSG) mice compared with cytokine-induced cells, and low-dose chemotherapy-based selection further increased engraftment. Long-term engraftment and the myeloid-to-lymphoid ratio achieved with vascular niche induction were similar to levels achieved for cord blood–derived MPP and up to 20-fold higher than those achieved with hPSC-derived MPP engraftment. Our findings indicate that endothelial Notch ligands promote PSC-definitive hematopoiesis and production of long-term engrafting CD34+ cells, suggesting these ligands are critical for HSC emergence. PMID:25664855

  18. Diabetes impairs adipose tissue-derived stem cell function and efficiency in promoting wound healing.

    PubMed

    Cianfarani, Francesca; Toietta, Gabriele; Di Rocco, Giuliana; Cesareo, Eleonora; Zambruno, Giovanna; Odorisio, Teresa

    2013-01-01

    Adipose tissue-derived stem cells (ASCs) are gaining increasing consideration in tissue repair therapeutic application. Recent evidence indicates that ASCs enhance skin repair in animal models of impaired wound healing. To assess the therapeutic activity of autologous vs. allogeneic ASCs in the treatment of diabetic ulcers, we functionally characterized diabetic ASCs and investigated their potential to promote wound healing with respect to nondiabetic ones. Adipose tissue-derived cells from streptozotocin-induced type 1 diabetic mice were analyzed either freshly isolated as stromal vascular fraction (SVF), or following a single passage of culture (ASCs). Diabetic ASCs showed decreased proliferative potential and migration. Expression of surface markers was altered in diabetic SVF and cultured ASCs, with a reduction in stem cell marker-positive cells. ASCs from diabetic mice released lower amounts of hepatocyte growth factor, vascular endothelial growth factor (VEGF)-A, and insulin-like growth factor-1, growth factors playing important roles in skin repair. Accordingly, the supernatant of diabetic ASCs manifested reduced capability to promote keratinocyte and fibroblast proliferation and migration. Therapeutic potential of diabetic SVF administered to wounds of diabetic mice was blunted as compared with cells isolated from nondiabetic mice. Our data indicate that diabetes alters ASC intrinsic properties and impairs their function, thus affecting therapeutic potential in the autologous treatment for diabetic ulcers. PMID:23627689

  19. Mesenchymal stem/progenitor cells promote the reconstitution of exogenous hematopoietic stem cells in Fancg−/− mice in vivo

    PubMed Central

    Li, Yan; Chen, Shi; Yuan, Jin; Yang, Yanzhu; Li, Jingling; Ma, Jin; Wu, Xiaohua; Freund, Marcel; Pollok, Karen; Hanenberg, Helmut; Goebel, W. Scott

    2009-01-01

    Fanconi anemia (FA) is a heterogeneous genetic disorder characterized by bone marrow failure and complex congenital anomalies. Although mutations in FA genes result in a characteristic phenotype in the hematopoietic stem/progenitor cells (HSPCs), little is known about the consequences of a nonfunctional FA pathway in other stem/progenitor cell compartments. Given the intense functional interactions between HSPCs and the mesenchymalmicroenvironment, we investigated the FA pathway on the cellular functions of murine mesenchymal stem/progenitor cells (MSPCs) and their interactions with HSPCs in vitro and in vivo. Here, we show that loss of the murine homologue of FANCG (Fancg) results in a defect in MSPC proliferation and in their ability to support the adhesion and engraftment of murine syngeneic HSPCs in vitro or in vivo. Transplantation of wild-type (WT) but not Fancg−/− MSPCs into the tibiae of Fancg−/− recipient mice enhances the HSPC engraftment kinetics, the BM cellularity, and the number of progenitors per tibia of WT HSPCs injected into lethally irradiated Fancg−/− recipients. Collectively, these data show that FA proteins are required in the BM microenvironment to maintain normal hematopoiesis and provide genetic and quantitative evidence that adoptive transfer of WT MSPCs enhances hematopoietic stem cell engraftment. PMID:19129541

  20. Heterochromatin protein 1 promotes self-renewal and triggers regenerative proliferation in adult stem cells.

    PubMed

    Zeng, An; Li, Yong-Qin; Wang, Chen; Han, Xiao-Shuai; Li, Ge; Wang, Jian-Yong; Li, Dang-Sheng; Qin, Yong-Wen; Shi, Yufang; Brewer, Gary; Jing, Qing

    2013-04-29

    Adult stem cells (ASCs) capable of self-renewal and differentiation confer the potential of tissues to regenerate damaged parts. Epigenetic regulation is essential for driving cell fate decisions by rapidly and reversibly modulating gene expression programs. However, it remains unclear how epigenetic factors elicit ASC-driven regeneration. In this paper, we report that an RNA interference screen against 205 chromatin regulators identified 12 proteins essential for ASC function and regeneration in planarians. Surprisingly, the HP1-like protein SMED-HP1-1 (HP1-1) specifically marked self-renewing, pluripotent ASCs, and HP1-1 depletion abrogated self-renewal and promoted differentiation. Upon injury, HP1-1 expression increased and elicited increased ASC expression of Mcm5 through functional association with the FACT (facilitates chromatin transcription) complex, which consequently triggered proliferation of ASCs and initiated blastema formation. Our observations uncover an epigenetic network underlying ASC regulation in planarians and reveal that an HP1 protein is a key chromatin factor controlling stem cell function. These results provide important insights into how epigenetic mechanisms orchestrate stem cell responses during tissue regeneration. PMID:23629965

  1. Tumor-promoting phorbol esters support the in vitro proliferation of murine pluripotent hematopoietic stem cells.

    PubMed Central

    Spivak, J L; Hogans, B B; Stuart, R K

    1989-01-01

    The effect of tumor-promoting phorbol esters on the in vitro proliferation of mouse pluripotent hematopoietic stem cells (CFU-S) was examined using a short-term in vitro culture system and an 11-d spleen colony assay. Phorbol myristate acetate (PMA, 10(-7) M), but not the inert compound phorbol, supported the in vitro survival of day 11 CFU-S for 72 h in a manner similar to IL 3. PMA also enhanced the effect of IL 3 on the in vitro survival of day 11 CFU-S and as little as 1 h of exposure to PMA was sufficient for this purpose. The effect of PMA on CFU-S survival in vitro was not mediated by prostaglandins, did not require an established adherent cell population, and was observed at a concentration of 10(-9) M. PMA alone did not enhance the in vitro survival of day 11 CFU-S at very low concentrations of FCS but was still able to potentiate the effect of IL 3 on these cells. PMA also enhanced the in vitro survival of day 11 CFU-S from mice treated with 5-fluorouracil or from marrow cells exposed to merocyanine 540 and light. The interaction of PMA with day 11 CFU-S was not inhibited by a neutralizing antiserum to IL 3 but was inhibited by the protein kinase inhibitor H-7. Together, the data indicate that tumor-promoting phorbol esters interact with pluripotent hematopoietic stem cells. Like IL 3, their effect appears to be permissive and involves stem cells with marrow repopulating ability. PMID:2463264

  2. EGFR signaling promotes self-renewal through the establishment of cell polarity in Drosophila follicle stem cells

    PubMed Central

    Castanieto, Angela; Johnston, Michael J; Nystul, Todd G

    2014-01-01

    Epithelial stem cells divide asymmetrically, such that one daughter replenishes the stem cell pool and the other differentiates. We found that, in the epithelial follicle stem cell (FSC) lineage of the Drosophila ovary, epidermal growth factor receptor (EGFR) signaling functions specifically in the FSCs to promote the unique partially polarized state of the FSC, establish apical–basal polarity throughout the lineage, and promote FSC maintenance in the niche. In addition, we identified a novel connection between EGFR signaling and the cell-polarity regulator liver kinase B1 (LKB1), which indicates that EGFR signals through both the Ras–Raf–MEK–Erk pathway and through the LKB1–AMPK pathway to suppress apical identity. The development of apical–basal polarity is the earliest visible difference between FSCs and their daughters, and our findings demonstrate that the EGFR-mediated regulation of apical–basal polarity is essential for the segregation of stem cell and daughter cell fates. DOI: http://dx.doi.org/10.7554/eLife.04437.001 PMID:25437306

  3. Ciliary neurotrophic factor promotes the activation of corneal epithelial stem/progenitor cells and accelerates corneal epithelial wound healing.

    PubMed

    Zhou, Qingjun; Chen, Peng; Di, Guohu; Zhang, Yangyang; Wang, Yao; Qi, Xia; Duan, Haoyun; Xie, Lixin

    2015-05-01

    Ciliary neurotrophic factor (CNTF), a well-known neuroprotective cytokine, has been found to play an important role in neurogenesis and functional regulations of neural stem cells. As one of the most innervated tissue, however, the role of CNTF in cornea epithelium remains unclear. This study was to explore the roles and mechanisms of CNTF in the activation of corneal epithelial stem/progenitor cells and wound healing of both normal and diabetic mouse corneal epithelium. In mice subjecting to mechanical removal of corneal epithelium, the corneal epithelial stem/progenitor cell activation and wound healing were promoted by exogenous CNTF application, while delayed by CNTF neutralizing antibody. In cultured corneal epithelial stem/progenitor cells, CNTF enhanced the colony-forming efficiency, stimulated the mitogenic proliferation, and upregulated the expression levels of corneal epithelial stem/progenitor cell-associated transcription factors. Furthermore, the promotion of CNTF on the corneal epithelial stem/progenitor cell activation and wound healing was mediated by the activation of STAT3. Moreover, in diabetic mice, the content of CNTF in corneal epithelium decreased significantly when compared with that of normal mice, and the supplement of CNTF promoted the diabetic corneal epithelial wound healing, accompanied with the advanced activation of corneal epithelial stem/progenitor cells and the regeneration of corneal nerve fibers. Thus, the capability of expanding corneal epithelial stem/progenitor cells and promoting corneal epithelial wound healing and nerve regeneration indicates the potential application of CNTF in ameliorating limbal stem cell deficiency and treating diabetic keratopathy. PMID:25546438

  4. Nicotine Promotes Acquisition of Stem Cell and Epithelial-to-Mesenchymal Properties in Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Rahimy, Elham; Haas, Martin; Yu, Vicky; Ellies, Lesley G.; Chen, Jing; Fan, Jian-Bing; Brumund, Kevin T.; Weisman, Robert A.; Ongkeko, Weg M.

    2012-01-01

    The ability of nicotine to enhance the malignancy of cancer cells is known; however, the possibility that nicotine could regulate a cancer stem cell phenotype remains to be well-established. In this study we sought to determine whether long-term exposure to nicotine could promote cancer stem cell-like properties in two head and neck squamous cell carcinoma cell lines, UMSCC-10B and HN-1. Nicotine treatment induced epithelial-to-mesenchymal transition (EMT) in both cell lines by repressing E-cadherin expression, and led to the induction of stem cell markers Oct-4, Nanog, CD44 and BMI-1, which was reversed upon ectopic re-expression of E-cadherin. Nicotine-treated cells formed spheres at a higher efficiency than non-treated cells, formed larger tumors when injected into mice, and formed tumors with 4-fold greater efficiency compared to control cells when injected at limiting doses. Consistent with previous literature, nicotine-treated cells demonstrated a greater capacity for survival and also a higher tendency to invade. Comparison of microRNA profiles between nicotine and control cells revealed the upregulation of miR-9, a repressor of E-cadherin, and the downregulation of miR-101, a repressor of EZH2. Taken together, these results suggest that nicotine may play a critical role in the development of tobacco-induced cancers by regulating cancer stem cell characteristics, and that these effects are likely mediated through EMT-promoting, microRNA-mediated pathways. Further characterization of such pathways remains a promising avenue for the understanding and treatment of tobacco-related cancers. PMID:23300583

  5. The chemokine receptor CCR7 promotes mammary tumorigenesis through amplification of stem-like cells.

    PubMed

    Boyle, S T; Ingman, W V; Poltavets, V; Faulkner, J W; Whitfield, R J; McColl, S R; Kochetkova, M

    2016-01-01

    The chemokine receptor CCR7 is widely implicated in breast cancer pathobiology. Although recent reports correlated high CCR7 levels with more advanced tumor grade and poor prognosis, limited in vivo data are available regarding its specific function in mammary gland neoplasia and the underlying mechanisms involved. To address these questions we generated a bigenic mouse model of breast cancer combined with CCR7 deletion, which revealed that CCR7 ablation results in a considerable delay in tumor onset as well as significantly reduced tumor burden. Importantly, CCR7 was found to exert its function by regulating mammary cancer stem-like cells in both murine and human tumors. In vivo experiments showed that loss of CCR7 activity either through deletion or pharmacological antagonism significantly decreased functional pools of stem-like cells in mouse primary mammary tumors, providing a mechanistic explanation for the tumor-promoting role of this chemokine receptor. These data characterize the oncogenic properties of CCR7 in mammary epithelial neoplasia and point to a new route for therapeutic intervention to target evasive cancer stem cells. PMID:25772241

  6. Dynamic hydrostatic pressure promotes differentiation of human dental pulp stem cells.

    PubMed

    Yu, V; Damek-Poprawa, M; Nicoll, S B; Akintoye, S O

    2009-09-01

    The masticatory apparatus absorbs high occlusal forces, but uncontrolled parafunctional or orthodontic forces damage periodontal ligament (PDL), cause pulpal calcification, pulp necrosis and tooth loss. Morphology and functional differentiation of connective tissue cells can be controlled by mechanical stimuli but effects of uncontrolled forces on intra-pulpal homeostasis and ability of dental pulp stem cells (DPSCs) to withstand direct external forces are unclear. Using dynamic hydrostatic pressure (HSP), we tested the hypothesis that direct HSP disrupts DPSC survival and odontogenic differentiation. DPSCs from four teenage patients were subjected to HSP followed by assessment of cell adhesion, survival and recovery capacity based on odontogenic differentiation, mineralization and responsiveness to bone morphogenetic protein-2 (BMP-2). HSP down-regulated DPSC adhesion and survival but promoted differentiation by increasing mineralization, in vivo hard tissue regeneration and BMP-2 responsiveness despite reduced cell numbers. HSP-treated DPSCs displayed enhanced odontogenic differentiation, an indication of favorable recovery from HSP-induced cellular stress. PMID:19555657

  7. Dynamic Hydrostatic Pressure Promotes Differentiation of Human Dental Pulp Stem Cells

    PubMed Central

    Yu, V; Damek-Poprawa, M.; Nicoll, S. B.; Akintoye, S.O.

    2009-01-01

    The masticatory apparatus absorbs high occlusal forces, but uncontrolled parafunctional or orthodontic forces damage periodontal ligament (PDL), cause pulpal calcification, pulp necrosis and tooth loss. Morphology and functional differentiation of connective tissue cells can be controlled by mechanical stimuli but effects of uncontrolled forces on intra-pulpal homeostasis and ability of dental pulp stem cells (DPSCs) to withstand direct external forces are unclear. Using dynamic hydrostatic pressure (HSP), we tested the hypothesis that direct HSP disrupts DPSC survival and odontogenic differentiation. DPSCs from four teenage patients were subjected to HSP followed by assessment of cell adhesion, survival and recovery capacity based on odontogenic differentiation, mineralization and responsiveness to bone morphogenetic protein-2 (BMP-2). HSP down-regulated DPSC adhesion and survival but promoted differentiation by increasing mineralization, in vivo hard tissue regeneration and BMP-2 responsiveness despite reduced cell numbers. HSP-treated DPSCs displayed enhanced odontogenic differentiation, an indication of favorable recovery from HSP-induced cellular stress. PMID:19555657

  8. Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

    SciTech Connect

    Li, Ying; Huang, Xiaohua; An, Yue; Ren, Feng; Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei; He, Xiaowen; Schachner, Melitta; Xiao, Zhicheng; Ma, Keli; Li, Yali

    2013-10-25

    Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression.

  9. Functional Analysis of Various Promoters in Lentiviral Vectors at Different Stages of In Vitro Differentiation of Mouse Embryonic Stem Cells

    PubMed Central

    Hong, Sunghoi; Hwang, Dong-Youn; Yoon, Soonsang; Isacson, Ole; Ramezani, Ali; Hawley, Robert G

    2008-01-01

    Given the therapeutic potential offered by embryonic stem (ES) cells, it is critical to optimize stable gene delivery and expression at different developmental stages of ES cell differentiation. Here, we systematically analyzed lentiviral vectors containing the following promoters: the human elongation factor 1α (EF1α) promoter, the human cytomegalovirus (CMV) immediate early region enhancer-promoter, the composite CAG promoter (consisting of the CMV immediate early enhancer and the chicken β-actin promoter), the human phosphoglycerate kinase 1 (PGK) promoter, the murine stem cell virus (MSCV) long terminal repeat (LTR), or the gibbon ape leukemia virus (GALV) LTR. Our results show that the EF1α promoter directed robust transgene expression at every stage of mouse ES cell differentiation, whereas the CMV promoter drove transgene expression only during late stages. Similarly, the CAG and PGK promoters drove transgene expression at a significant level only during late stages. The MSCV LTR and the GALV LTR exhibited much lower promoter activities at all stages. Interestingly, mouse ES cells transduced with the EF1α promoter-containing lentiviral vector lost most of their transgene expression during in vitro differentiation to neural precursors and neuronal cells. Our results demonstrate that different cellular and viral promoters exhibit very distinct and dynamic properties not only in terms of promoter strength but also with respect to differentiation stage-specific activity. PMID:17609656

  10. Polysaccharide Hydrogel Combined with Mesenchymal Stem Cells Promotes the Healing of Corneal Alkali Burn in Rats

    PubMed Central

    Liu, Xun; Yu, Min; Yang, Chunbo; Li, Xiaorong

    2015-01-01

    Corneal chemical burns are common ophthalmic injuries that may result in permanent visual impairment. Although significant advances have been achieved on the treatment of such cases, the structural and functional restoration of a chemical burn-injured cornea remains challenging. The applications of polysaccharide hydrogel and subconjunctival injection of mesenchymal stem cells (MSCs) have been reported to promote the healing of corneal wounds. In this study, polysaccharide was extracted from Hardy Orchid and mesenchymal stem cells (MSCs) were derived from Sprague-Dawley rats. Supplementation of the polysaccharide significantly enhanced the migration rate of primarily cultured rat corneal epithelial cells. We examined the therapeutic effects of polysaccharide in conjunction with MSCs application on the healing of corneal alkali burns in rats. Compared with either treatment alone, the combination strategy resulted in significantly better recovery of corneal epithelium and reduction in inflammation, neovascularization and opacity of healed cornea. Polysaccharide and MSCs acted additively to increase the expression of anti-inflammatory cytokine (TGF-β), antiangiogenic cytokine (TSP-1) and decrease those promoting inflammation (TNF-α), chemotaxis (MIP-1α and MCP-1) and angiogenesis (VEGF and MMP-2). This study provided evidence that Hardy Orchid derived polysaccharide and MSCs are safe and effective treatments for corneal alkali burns and that their benefits are additive when used in combination. We concluded that combination therapy with polysaccharide and MSCs is a promising clinical treatment for corneal alkali burns and may be applicable for other types of corneal disorder. PMID:25789487

  11. Human mesenchymal stem cells creating an immunosuppressive environment and promote breast cancer in mice.

    PubMed

    Ljujic, Biljana; Milovanovic, Marija; Volarevic, Vladislav; Murray, Bridgid; Bugarski, Diana; Przyborski, Stefan; Arsenijevic, Nebojsa; Lukic, Miodrag L; Stojkovic, Miodrag

    2013-01-01

    Human mesenchymal stem cells (hMSC) can home to tumor sites and promote tumor growth. The effects of hMSC on tumor growth are controversial and involvement of hMSC in tumor immunology has not been adequately addressed. Therefore, we investigated whether injection of hMSC affects tumor appearance, growth and metastasis, and anti-tumor immunity in an experimental animal model of metastatic breast cancer. Injection of hMSC in BALB/c mice bearing mammary carcinoma promoted tumor growth and metastasis, which was accompanied by lower cytotoxic activity of splenocytes, NK cells and CD8⁺ T cells in vitro. Tumor-bearing mice that received hMSC had significantly lower percentages of CD3⁺NKp46⁺ NKT-like, higher percentages of CD4⁺Foxp3⁺ T cells, increased serum levels of Th2 and decreased serum levels of Th1 cytokines, and significantly higher number of CD4⁺ cells expressing IL-10. These results demonstrate that immunosuppressive environment created by hMSC promoted breast tumor growth and metastasis in mice. PMID:23892388

  12. Human mesenchymal stem cells creating an immunosuppressive environment and promote breast cancer in mice

    PubMed Central

    Ljujic, Biljana; Milovanovic, Marija; Volarevic, Vladislav; Murray, Bridgid; Bugarski, Diana; Przyborski, Stefan; Arsenijevic, Nebojsa; Lukic, Miodrag L.; Stojkovic, Miodrag

    2013-01-01

    Human mesenchymal stem cells (hMSC) can home to tumor sites and promote tumor growth. The effects of hMSC on tumor growth are controversial and involvement of hMSC in tumor immunology has not been adequately addressed. Therefore, we investigated whether injection of hMSC affects tumor appearance, growth and metastasis, and anti-tumor immunity in an experimental animal model of metastatic breast cancer. Injection of hMSC in BALB/c mice bearing mammary carcinoma promoted tumor growth and metastasis, which was accompanied by lower cytotoxic activity of splenocytes, NK cells and CD8+ T cells in vitro. Tumor-bearing mice that received hMSC had significantly lower percentages of CD3+NKp46+ NKT-like, higher percentages of CD4+Foxp3+ T cells, increased serum levels of Th2 and decreased serum levels of Th1 cytokines, and significantly higher number of CD4+ cells expressing IL-10. These results demonstrate that immunosuppressive environment created by hMSC promoted breast tumor growth and metastasis in mice. PMID:23892388

  13. VEGF and BMP-2 promote bone regeneration by facilitating bone marrow stem cell homing and differentiation.

    PubMed

    Zhang, W; Zhu, C; Wu, Y; Ye, D; Wang, S; Zou, D; Zhang, X; Kaplan, D L; Jiang, X

    2014-01-01

    Vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) have been widely used in the fields of tissue engineering and regenerative medicine to stimulate angiogenesis and bone formation. The goal of this study was to determine whether VEGF and BMP-2 are involved in the homing of bone marrow stem cells (BMSCs) for bone regeneration and to provide insights into their mechanism of action. The chemoattraction of BMSCs to VEGF and BMP-2 was analysed in vitro using a checkerboard assay. VEGF and BMP-2 stimulated the chemotaxis of BMSCs but not chemokinesis. In vivo, both VEGF and BMP-2 also have been confirmed to induce the homing of tail vein injected BMSCs to the site of silk scaffold subcutaneous implantation in nude mice. When the scaffolds were implanted in the rabbit skull defects, more SSEA+ mesenchymal stem cells were mobilised and homed to silk scaffolds containing VEGF and/or BMP-2. More importantly, autogenic BMSCs were reinjected via the ear vein after labelling with lenti-GFP, and the cells were detected to home to the defects and differentiate into endothelial cells and osteogenic cells induced by VEGF and BMP-2. Finally, perfusion with Microfil showed that initial angiogenesis was enhanced in tissue-engineered complexes containing VEGF. Observations based on µCT assay and histological study revealed that bone formation was accelerated on BMP-2-containing scaffolds. These findings support our hypothesis that the localised release of VEGF and BMP-2 promote bone regeneration, in part by facilitating the mobilisation of endogenous stem cells and directing the differentiation of these cells into endothelial and osteogenic lineages. PMID:24425156

  14. Dasatinib promotes the activation of quiescent hematopoietic stem cells in mice.

    PubMed

    Duyvestyn, Johanna M; Taylor, Samuel J; Dagger, Samantha A; Langdon, Wallace Y

    2016-05-01

    Dasatinib is an orally available broad-spectrum tyrosine kinase inhibitor that is widely used to treat chronic myeloid leukemia. It is also in clinical trials for the treatment of other malignancies, including solid tumors. Despite its wide use, little is known of its effects on normal hematopoietic stem and progenitor cells. Here, we study wild-type mice dosed with dasatinib and find that it causes the transient induction of proliferation of quiescent hematopoietic stem cells (HSCs). This finding was unexpected given the ability of dasatinib to inhibit c-Kit signaling and promote cell cycle arrest in many cell types. The transient induction of HSC proliferation in dasatinib-dosed mice coincided with a marked induction in the expression of Sca-1 and phospho-S6. Also evident at this time was a rapid but transient loss of lineage-committed hematopoietic progenitors that express high levels of c-Kit and the induction of stem cell factor in the serum. These findings suggest that activation of quiescent HSCs is part of a rapid rescue response that restores hematopoietic progenitors to pretreatment levels. This restoration coincides with HSCs returning to quiescence, and the expression of Sca-1 and phospho-S6 reverting to pre-treatment levels, even though dasatinib dosing is maintained. These data suggest that equilibrium is reached between the opposing forces of dasatinib and hematopoietic growth factors. The transient induction of HSC proliferation provided a window of opportunity whereby these cells became sensitive to killing by the cytotoxic drug 5-fluorouracil. PMID:26921649

  15. Human umbilical mesenchymal stem cells conditioned medium promote primary wound healing regeneration

    PubMed Central

    Kusindarta, Dwi Liliek; Wihadmadyatami, Hevi; Fibrianto, Yuda Heru; Nugroho, Widagdo Sri; Susetya, Heru; Musana, Dewi Kania; Wijayanto, Hery; Prihatna, Surya Agus; Wahyuni, A. E. T. H.

    2016-01-01

    Aim: This research was conducted to clarify the capability of human umbilical mesenchymal stem cells conditioned medium (HU-MSCM) to promote regenerations of primary wound healing on the incision skin injury. Materials and Methods: In this study, two approaches in vitro and in vivo already done. On in vitro analysis, tube formation was performed using HU vein endothelial cells in the presence of HU-MSCM, in some experiments cells line was incubated prior the presence of lipopolysaccharide and HU-MSCM then apoptosis assay was performed. Furthermore, in vivo experiments 12 female rats (Rattus norvegicus) were used after rats anesthetized, 7 mm wound was made by incision on the left side of the body. The wound was treated with HU-MSCM containing cream, povidone iodine was run as a control. Wound healing regenerations on the skin samples were visualized by hematoxylin-eosin staining. Results: In vitro models elucidate HU-MSCM may decreasing inflammation at the beginning of wound healing, promote cell migration and angiogenesis. In addition in vivo models show that the incision length on the skin is decreasing and more smaller, HE staining describe decreasing of inflammation phase, increasing of angiogenesis, accelerate fibroplasia, and maturation phase. Conclusions: Taken together our observation indicates that HU-MSCM could promote the acceleration of skin tissue regenerations in primary wound healing process. PMID:27397984

  16. XB130 promotes bronchioalveolar stem cell and Club cell proliferation in airway epithelial repair and regeneration

    PubMed Central

    Toba, Hiroaki; Wang, Yingchun; Bai, Xiaohui; Zamel, Ricardo; Cho, Hae-Ra; Liu, Hongmei; Lira, Alonso; Keshavjee, Shaf; Liu, Mingyao

    2015-01-01

    Proliferation of bronchioalveolar stem cells (BASCs) is essential for epithelial repair. XB130 is a novel adaptor protein involved in the regulation of epithelial cell survival, proliferation and migration through the PI3K/Akt pathway. To determine the role of XB130 in airway epithelial injury repair and regeneration, a naphthalene-induced airway epithelial injury model was used with XB130 knockout (KO) mice and their wild type (WT) littermates. In XB130 KO mice, at days 7 and 14, small airway epithelium repair was significantly delayed with fewer number of Club cells (previously called Clara cells). CCSP (Club cell secreted protein) mRNA expression was also significantly lower in KO mice at day 7. At day 5, there were significantly fewer proliferative epithelial cells in the KO group, and the number of BASCs significantly increased in WT mice but not in KO mice. At day 7, phosphorylation of Akt, GSK-3β, and the p85α subunit of PI3K was observed in airway epithelial cells in WT mice, but to a much lesser extent in KO mice. Microarray data also suggest that PI3K/Akt-related signals were regulated differently in KO and WT mice. An inhibitory mechanism for cell proliferation and cell cycle progression was suggested in KO mice. XB130 is involved in bronchioalveolar stem cell and Club cell proliferation, likely through the PI3K/Akt/GSK-3β pathway. PMID:26360608

  17. Combinatorial polymer electrospun matrices promote physiologically-relevant cardiomyogenic stem cell differentiation.

    PubMed

    Gupta, Mukesh K; Walthall, Joel M; Venkataraman, Raghav; Crowder, Spencer W; Jung, Dae Kwang; Yu, Shann S; Feaster, Tromondae K; Wang, Xintong; Giorgio, Todd D; Hong, Charles C; Baudenbacher, Franz J; Hatzopoulos, Antonis K; Sung, Hak-Joon

    2011-01-01

    Myocardial infarction results in extensive cardiomyocyte death which can lead to fatal arrhythmias or congestive heart failure. Delivery of stem cells to repopulate damaged cardiac tissue may be an attractive and innovative solution for repairing the damaged heart. Instructive polymer scaffolds with a wide range of properties have been used extensively to direct the differentiation of stem cells. In this study, we have optimized the chemical and mechanical properties of an electrospun polymer mesh for directed differentiation of embryonic stem cells (ESCs) towards a cardiomyogenic lineage. A combinatorial polymer library was prepared by copolymerizing three distinct subunits at varying molar ratios to tune the physicochemical properties of the resulting polymer: hydrophilic polyethylene glycol (PEG), hydrophobic poly(ε-caprolactone) (PCL), and negatively-charged, carboxylated PCL (CPCL). Murine ESCs were cultured on electrospun polymeric scaffolds and their differentiation to cardiomyocytes was assessed through measurements of viability, intracellular reactive oxygen species (ROS), α-myosin heavy chain expression (α-MHC), and intracellular Ca(2+) signaling dynamics. Interestingly, ESCs on the most compliant substrate, 4%PEG-86%PCL-10%CPCL, exhibited the highest α-MHC expression as well as the most mature Ca(2+) signaling dynamics. To investigate the role of scaffold modulus in ESC differentiation, the scaffold fiber density was reduced by altering the electrospinning parameters. The reduced modulus was found to enhance α-MHC gene expression, and promote maturation of myocyte Ca(2+) handling. These data indicate that ESC-derived cardiomyocyte differentiation and maturation can be promoted by tuning the mechanical and chemical properties of polymer scaffold via copolymerization and electrospinning techniques. PMID:22216144

  18. Formylpeptide Receptors Promote the Migration and Differentiation of Rat Neural Stem Cells

    PubMed Central

    Wang, Guan; Zhang, Liang; Chen, Xingxing; Xue, Xin; Guo, Qiaonan; Liu, Mingyong; Zhao, Jianhua

    2016-01-01

    Neural stem cells (NSCs) bear characteristics for proliferation, migration and differentiation into three main neural cell type(s): neurons, astrocytes and/or oligodendrocytes. Formylpeptide receptors (Fprs), belonging to the family of G protein-coupled chemoattractant receptors, have been detected on neurons in the central nervous system (CNS). Here, we report that Fpr1 and Fpr2 are expressed on NSCs as detected with immunohistochemistry, RT-PCR and WB assays. In addition, Fpr1 and Fpr2 promoted NSC migration through F-actin polymerization and skewed NSC differentiation to neurons. Our study demonstrates a unique role of Fpr1 and Fpr2 in NSCs and opens a novel window for cell replacement therapies for brain and spinal cord injury. PMID:27173446

  19. DNA damage-induced type I interferon promotes senescence and inhibits stem cell function

    PubMed Central

    Carbone, Christopher J.; Zhao, Bin; Katlinski, Kanstantsin V.; Zheng, Hui; Guha, Manti; Li, Ning; Chen, Qijun; Yang, Ting; Lengner, Christopher J.; Greenberg, Roger A.; Johnson, F. Brad; Fuchs, Serge Y.

    2015-01-01

    Expression of type I interferons (IFN) can be induced by DNA damaging agents but the mechanisms and significance of this regulation are not completely understood. We found that the transcription factor IRF3, activated in an ATM-IKKα/β dependent manner, stimulates cell-autonomous IFNβ expression in response to double-stranded DNA breaks. Cells and tissues with accumulating DNA damage produce endogenous IFNβ and stimulate IFN signaling in vitro and in vivo. In turn, IFN acts to amplify DNA damage responses, activate the p53 pathway, promote senescence and inhibit stem cells function in response to telomere shortening. Inactivation of the IFN pathway abrogates the development of diverse progeric phenotypes and extends the life span of Terc knockout mice. These data identify DNA damage response-induced IFN signaling as a critical mechanism that links accumulating DNA damage with senescence and premature aging. PMID:25921537

  20. Formylpeptide Receptors Promote the Migration and Differentiation of Rat Neural Stem Cells.

    PubMed

    Wang, Guan; Zhang, Liang; Chen, Xingxing; Xue, Xin; Guo, Qiaonan; Liu, Mingyong; Zhao, Jianhua

    2016-01-01

    Neural stem cells (NSCs) bear characteristics for proliferation, migration and differentiation into three main neural cell type(s): neurons, astrocytes and/or oligodendrocytes. Formylpeptide receptors (Fprs), belonging to the family of G protein-coupled chemoattractant receptors, have been detected on neurons in the central nervous system (CNS). Here, we report that Fpr1 and Fpr2 are expressed on NSCs as detected with immunohistochemistry, RT-PCR and WB assays. In addition, Fpr1 and Fpr2 promoted NSC migration through F-actin polymerization and skewed NSC differentiation to neurons. Our study demonstrates a unique role of Fpr1 and Fpr2 in NSCs and opens a novel window for cell replacement therapies for brain and spinal cord injury. PMID:27173446

  1. ZEB1 Promotes Invasion in Human Fetal Neural Stem Cells and Hypoxic Glioma Neurospheres.

    PubMed

    Kahlert, Ulf D; Suwala, Abigail K; Raabe, Eric H; Siebzehnrubl, Florian A; Suarez, Maria J; Orr, Brent A; Bar, Eli E; Maciaczyk, Jaroslaw; Eberhart, Charles G

    2015-11-01

    Diffuse spread through brain parenchyma and the presence of hypoxic foci rimmed by neoplastic cells are two cardinal features of glioblastoma, and low oxygen is thought to drive movement of malignant gliomas in the core of the lesions. Transcription factors associated with epithelial-to-mesenchymal transition (EMT) have been linked to this invasion, and we found that hypoxia increased in vitro invasion up to fourfold in glioblastoma neurosphere lines and induced the expression of ZEB1. Immunohistochemical assessment of 295 surgical specimens consisting of various types of pediatric and adult brain cancers showed that ZEB1 expression was significantly higher in infiltrative lesions than less invasive tumors such as pilocytic astrocytoma and ependymoma. ZEB1 protein was also present in human fetal periventricular stem and progenitor cells and ZEB1 inhibition impaired migration of in vitro propagated human neural stem cells. The induction of ZEB1 protein in hypoxic glioblastoma neurospheres could be partially blocked by the HIF1alpha inhibitor digoxin. Targeting ZEB1 blocked hypoxia-augmented invasion of glioblastoma cells in addition to slowing them in normoxia. These data support the role for ZEB1 in invasive and high-grade brain tumors and suggest its key role in promoting invasion in the hypoxic tumor core as well as in the periphery. PMID:25521330

  2. Drug-based modulation of endogenous stem cells promotes functional remyelination in vivo.

    PubMed

    Najm, Fadi J; Madhavan, Mayur; Zaremba, Anita; Shick, Elizabeth; Karl, Robert T; Factor, Daniel C; Miller, Tyler E; Nevin, Zachary S; Kantor, Christopher; Sargent, Alex; Quick, Kevin L; Schlatzer, Daniela M; Tang, Hong; Papoian, Ruben; Brimacombe, Kyle R; Shen, Min; Boxer, Matthew B; Jadhav, Ajit; Robinson, Andrew P; Podojil, Joseph R; Miller, Stephen D; Miller, Robert H; Tesar, Paul J

    2015-06-11

    Multiple sclerosis involves an aberrant autoimmune response and progressive failure of remyelination in the central nervous system. Prevention of neural degeneration and subsequent disability requires remyelination through the generation of new oligodendrocytes, but current treatments exclusively target the immune system. Oligodendrocyte progenitor cells are stem cells in the central nervous system and the principal source of myelinating oligodendrocytes. These cells are abundant in demyelinated regions of patients with multiple sclerosis, yet fail to differentiate, thereby representing a cellular target for pharmacological intervention. To discover therapeutic compounds for enhancing myelination from endogenous oligodendrocyte progenitor cells, we screened a library of bioactive small molecules on mouse pluripotent epiblast stem-cell-derived oligodendrocyte progenitor cells. Here we show seven drugs function at nanomolar doses selectively to enhance the generation of mature oligodendrocytes from progenitor cells in vitro. Two drugs, miconazole and clobetasol, are effective in promoting precocious myelination in organotypic cerebellar slice cultures, and in vivo in early postnatal mouse pups. Systemic delivery of each of the two drugs significantly increases the number of new oligodendrocytes and enhances remyelination in a lysolecithin-induced mouse model of focal demyelination. Administering each of the two drugs at the peak of disease in an experimental autoimmune encephalomyelitis mouse model of chronic progressive multiple sclerosis results in striking reversal of disease severity. Immune response assays show that miconazole functions directly as a remyelinating drug with no effect on the immune system, whereas clobetasol is a potent immunosuppressant as well as a remyelinating agent. Mechanistic studies show that miconazole and clobetasol function in oligodendrocyte progenitor cells through mitogen-activated protein kinase and glucocorticoid receptor

  3. Bone marrow-derived mesenchymal stem cells promote growth and angiogenesis of breast and prostate tumors

    PubMed Central

    2013-01-01

    Introduction Mesenchymal stem cells (MSCs) are known to migrate to tumor tissues. This behavior of MSCs has been exploited as a tumor-targeting strategy for cell-based cancer therapy. However, the effects of MSCs on tumor growth are controversial. This study was designed to determine the effect of MSCs on the growth of breast and prostate tumors. Methods Bone marrow-derived MSCs (BM-MSCs) were isolated and characterized. Effects of BM-MSCs on tumor cell proliferation were analyzed in a co-culture system with mouse breast cancer cell 4T1 or human prostate cancer cell DU145. Tumor cells were injected into nude mice subcutaneously either alone or coupled with BM-MSCs. The expression of cell proliferation and angiogenesis-related proteins in tumor tissues were immunofluorescence analyzed. The angiogenic effect of BM-MSCs was detected using a tube formation assay. The effects of the crosstalk between tumor cells and BM-MSCs on expression of angiogenesis related markers were examined by immunofluorescence and real-time PCR. Results Both co-culturing with mice BM-MSCs (mBM-MSCs) and treatment with mBM-MSC-conditioned medium enhanced the growth of 4T1 cells. Co-injection of 4T1 cells and mBM-MSCs into nude mice led to increased tumor size compared with injection of 4T1 cells alone. Similar experiments using DU145 cells and human BM-MSCs (hBM-MSCs) instead of 4T1 cells and mBM-MSCs obtained consistent results. Compared with tumors induced by injection of tumor cells alone, the blood vessel area was greater in tumors from co-injection of tumor cells with BM-MSCs, which correlated with decreased central tumor necrosis and increased tumor cell proliferation. Furthermore, both conditioned medium from hBM-MSCs alone and co-cultures of hBM-MSCs with DU145 cells were able to promote tube formation ability of human umbilical vein endothelial cells. When hBM-MSCs are exposed to the DU145 cell environment, the expression of markers associated with neovascularization (macrophage

  4. Laminin 411 and 511 promote the cholangiocyte differentiation of human induced pluripotent stem cells.

    PubMed

    Takayama, Kazuo; Mitani, Seiji; Nagamoto, Yasuhito; Sakurai, Fuminori; Tachibana, Masashi; Taniguchi, Yukimasa; Sekiguchi, Kiyotoshi; Mizuguchi, Hiroyuki

    2016-05-20

    The drug discovery research for cholestatic liver diseases has been hampered by the lack of a well-established human cholangiocyte model. Functional cholangiocyte-like cells differentiated from human induced pluripotent stem (iPS) cells are expected to be a promising candidate for such research, but there remains no well-established method for differentiating cholangiocytes from human iPS cells. In this study, we searched for a suitable extracellular matrix to promote cholangiocyte differentiation from human iPS cells, and found that both laminin 411 and laminin 511 were suitable for this purpose. The gene expression levels of the cholangiocyte markers, aquaporin 1 (AQP1), SRY-box 9 (SOX9), cystic fibrosis transmembrane conductance regulator (CFTR), G protein-coupled bile acid receptor 1 (GPBAR1), Jagged 1 (JAG1), secretin receptor (SCTR), and γ-glutamyl transferase (GGT1) were increased by using laminin 411 or laminin 511 as a matrix. In addition, the percentage of AQP1-positive cells was increased from 61.8% to 92.5% by using laminin 411 or laminin 511. Furthermore, the diameter and number of cysts consisted of cholangiocyte-like cells were increased when using either matrix. We believe that the human iPS cell-derived cholangiocyte-like cells, which were generated by using our differentiation technology, would be useful for the drug discovery research of cholestatic liver diseases. PMID:27103433

  5. Thymosin beta-4 promotes mesenchymal stem cell proliferation via an interleukin-8-dependent mechanism

    SciTech Connect

    Jeon, Byung-Joon; Yang, Yoolhee; Kyung Shim, Su; Yang, Heung-Mo; Cho, Daeho; Ik Bang, Sa

    2013-10-15

    Mesenchymal stem cells (MSCs) hold great promise for the field of tissue regeneration. Because only a limited number of MSCs can be obtained from each donor site, it is important to establish standard methods for MSC expansion using growth and trophic factors. Thymosin β4 (Tβ4) is a novel trophic factor that has antimicrobial effects and the potential to promote tissue repair. Tβ4 is a ubiquitous, naturally-occurring peptide in the wound bed. Therefore, the relationship between Tβ4 and MSCs, especially adjacent adipose tissue-derived stem cells (ASCs), merits consideration. Exogenous Tβ4 treatment enhanced the proliferation of human ASCs, resulting in prominent nuclear localization of PCNA immunoreactivity. In addition, exogenous Tβ4 also increased IL-8 secretion and blocking of IL-8 with neutralizing antibodies decreased Tβ4-induced ASC proliferation, suggesting that IL-8 is a critical mediator of Tβ4-enhanced proliferation. Moreover, Tβ4 activated phosphorylation of ERK1/2 and increased the nuclear translocation of NF-κB. These observation provide that Tβ4 promotes the expansion of human ASCs via an IL-8-dependent mechanism that involves the ERK and NF-κB pathways. Therefore, Tβ4 could be used as a tool for MSC expansion in cell therapeutics. - Highlights: • This is fundamental information required to correlate Tβ4 with MSC expansion. • MSC expansion by Tβ4 is involved in enhancement of IL-8 and ERK/NF-κB pathway. • Tβ4 could be used as a tool for MSC expansion in cell therapeutics.

  6. Nanoparticle-facilitated autophagy inhibition promotes the efficacy of chemotherapeutics against breast cancer stem cells.

    PubMed

    Sun, Rong; Shen, Song; Zhang, Yun-Jiao; Xu, Cong-Fei; Cao, Zhi-Ting; Wen, Long-Ping; Wang, Jun

    2016-10-01

    Cancer stem cells (CSCs) have garnered increasing attention over the past decade, as they are believed to play a crucial role in tumor initiation, progression and metastasis, relapse and drug resistance. Therapeutic strategies which simultaneously exterminate both bulk tumor cells and the rare CSC subpopulation may produce striking response and result in long-term tumor remission. Accumulating evidence provides insight into the function of autophagy in maintenance, plasticity and survival of CSCs. The role of autophagy in the susceptibility of breast CSCs to chemotherapeutics was investigated in the present work, reduced 'stemness' and increased susceptibility to chemotherapy drugs (doxorubicin, DOX and docetaxel, DTXL) were observed after chloroquine (CQ)-mediated autophagy inhibition in sorted ALDH(hi) cells of breast cancer cell line MDA-MB-231. We further proved that nanoparticle-mediated autophagy inhibition promoted the efficacy of chemotherapeutics against ALDH(hi) MDA-MB-231 cells in vitro. Administration of drug delivery systems significantly prolonged the circulation half-life and augmented enrichment of two different drugs in tumor tissues and ALDH(hi) cells. More importantly, compared with single treatment, the combined delivery systems NPCQ/NPDOX and NPCQ/DOX (NPCQ/NPDTXL and NPCQ/DTXL) showed most effective and persistent tumor growth inhibitory effect by eliminating bulk tumor cells as well as CSCs (p < 0.01) in an MDA-MB-231 orthotopic tumor murine model. Therefore, our research provides new insights into the nanoparticle-facilitated combination of autophagy inhibition and chemotherapy for effective therapy of breast cancer. PMID:27376558

  7. Chinese preparation Xuesaitong promotes the mobilization of bone marrow mesenchymal stem cells in rats with cerebral infarction.

    PubMed

    Zhang, Jin-Sheng; Zhang, Bao-Xia; Du, Mei-Mei; Wang, Xiao-Ya; Li, Wei

    2016-02-01

    After cerebral ischemia, bone marrow mesenchymal stem cells are mobilized and travel from the bone marrow through peripheral circulation to the focal point of ischemia to initiate tissue regeneration. However, the number of bone marrow mesenchymal stem cells mobilized into peripheral circulation is not enough to exert therapeutic effects, and the method by which blood circulation is promoted to remove blood stasis influences stem cell homing. The main ingredient of Xuesaitong capsules is Panax notoginseng saponins, and Xuesaitong is one of the main drugs used for promoting blood circulation and removing blood stasis. We established rat models of cerebral infarction by occlusion of the middle cerebral artery and then intragastrically administered Xuesaitong capsules (20, 40 and 60 mg/kg per day) for 28 successive days. Enzyme-linked immunosorbent assay showed that in rats with cerebral infarction, middle- and high-dose Xuesaitong significantly increased the level of stem cell factors and the number of CD117-positive cells in plasma and bone marrow and significantly decreased the number of CD54- and CD106-positive cells in plasma and bone marrow. The effect of low-dose Xuesaitong on these factors was not obvious. These findings demonstrate that middle- and high-dose Xuesaitong and hence Panax notoginseng saponins promote and increase the level and mobilization of bone marrow mesenchymal stem cells in peripheral blood. PMID:27073383

  8. Chinese preparation Xuesaitong promotes the mobilization of bone marrow mesenchymal stem cells in rats with cerebral infarction

    PubMed Central

    Zhang, Jin-sheng; Zhang, Bao-xia; Du, Mei-mei; Wang, Xiao-ya; Li, Wei

    2016-01-01

    After cerebral ischemia, bone marrow mesenchymal stem cells are mobilized and travel from the bone marrow through peripheral circulation to the focal point of ischemia to initiate tissue regeneration. However, the number of bone marrow mesenchymal stem cells mobilized into peripheral circulation is not enough to exert therapeutic effects, and the method by which blood circulation is promoted to remove blood stasis influences stem cell homing. The main ingredient of Xuesaitong capsules is Panax notoginseng saponins, and Xuesaitong is one of the main drugs used for promoting blood circulation and removing blood stasis. We established rat models of cerebral infarction by occlusion of the middle cerebral artery and then intragastrically administered Xuesaitong capsules (20, 40 and 60 mg/kg per day) for 28 successive days. Enzyme-linked immunosorbent assay showed that in rats with cerebral infarction, middle- and high-dose Xuesaitong significantly increased the level of stem cell factors and the number of CD117-positive cells in plasma and bone marrow and significantly decreased the number of CD54- and CD106-positive cells in plasma and bone marrow. The effect of low-dose Xuesaitong on these factors was not obvious. These findings demonstrate that middle- and high-dose Xuesaitong and hence Panax notoginseng saponins promote and increase the level and mobilization of bone marrow mesenchymal stem cells in peripheral blood. PMID:27073383

  9. Nucleostemin maintains self-renewal of embryonic stem cells and promotes reprogramming of somatic cells to pluripotency

    PubMed Central

    Bishop, J. Michael

    2012-01-01

    Nucleostemin (NS) is a nucleolar GTP-binding protein that was first identified in neural stem cells, the functions of which remain poorly understood. Here, we report that NS is required for mouse embryogenesis to reach blastulation, maintenance of embryonic stem cell (ESC) self-renewal, and mammary epithelial cell (MEC) reprogramming to induced pluripotent stem (iPS) cells. Ectopic NS also cooperates with OCT4 and SOX2 to reprogram MECs and mouse embryonic fibroblasts to iPS cells. NS promotes ESC self-renewal by sustaining rapid transit through the G1 phase of the cell cycle. Depletion of NS in ESCs retards transit through G1 and induces gene expression changes and morphological differentiation through a mechanism that involves the MEK/ERK protein kinases and that is active only during a protracted G1. Suppression of cell cycle inhibitors mitigates these effects. Our results implicate NS in the maintenance of ESC self-renewal, demonstrate the importance of rapid transit through G1 for this process, and expand the known classes of reprogramming factors. PMID:22689653

  10. Stem Cell Basics

    MedlinePlus

    ... stem cells? What are the potential uses of human stem cells and the obstacles that must be overcome before ... two kinds of stem cells from animals and humans: embryonic stem cells and non-embryonic "somatic" or "adult" stem cells . ...

  11. Learn About Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... ISSCR Get Involved Media © 2015 International Society for Stem Cell Research Terms of Use Disclaimer Privacy Policy

  12. Sostdc1 deficiency accelerates fracture healing by promoting the expansion of periosteal mesenchymal stem cells.

    PubMed

    Collette, Nicole M; Yee, Cristal S; Hum, Nicholas R; Murugesh, Deepa K; Christiansen, Blaine A; Xie, LiQin; Economides, Aris N; Manilay, Jennifer O; Robling, Alexander G; Loots, Gabriela G

    2016-07-01

    Loss of Sostdc1, a growth factor paralogous to Sost, causes the formation of ectopic incisors, fused molars, abnormal hair follicles, and resistance to kidney disease. Sostdc1 is expressed in the periosteum, a source of osteoblasts, fibroblasts and mesenchymal progenitor cells, which are critically important for fracture repair. Here, we investigated the role of Sostdc1 in bone metabolism and fracture repair. Mice lacking Sostdc1 (Sostdc1(-/-)) had a low bone mass phenotype associated with loss of trabecular bone in both lumbar vertebrae and in the appendicular skeleton. In contrast, Sostdc1(-/-) cortical bone measurements revealed larger bones with higher BMD, suggesting that Sostdc1 exerts differential effects on cortical and trabecular bone. Mid-diaphyseal femoral fractures induced in Sostdc1(-/-) mice showed that the periosteal population normally positive for Sostdc1 rapidly expands during periosteal thickening and these cells migrate into the fracture callus at 3days post fracture. Quantitative analysis of mesenchymal stem cell (MSC) and osteoblast populations determined that MSCs express Sostdc1, and that Sostdc1(-/-) 5day calluses harbor >2-fold more MSCs than fractured wildtype controls. Histologically a fraction of Sostdc1-positive cells also expressed nestin and α-smooth muscle actin, suggesting that Sostdc1 marks a population of osteochondral progenitor cells that actively participate in callus formation and bone repair. Elevated numbers of MSCs in D5 calluses resulted in a larger, more vascularized cartilage callus at day 7, and a more rapid turnover of cartilage with significantly more remodeled bone and a thicker cortical shell at 21days post fracture. These data support accelerated or enhanced bone formation/remodeling of the callus in Sostdc1(-/-) mice, suggesting that Sostdc1 may promote and maintain mesenchymal stem cell quiescence in the periosteum. PMID:27102547

  13. MAPK/ERK2 phosphorylates ERG at serine 283 in leukemic cells and promotes stem cell signatures and cell proliferation.

    PubMed

    Huang, Y; Thoms, J A I; Tursky, M L; Knezevic, K; Beck, D; Chandrakanthan, V; Suryani, S; Olivier, J; Boulton, A; Glaros, E N; Thomas, S R; Lock, R B; MacKenzie, K L; Bushweller, J H; Wong, J W H; Pimanda, J E

    2016-07-01

    Aberrant ERG (v-ets avian erythroblastosis virus E26 oncogene homolog) expression drives leukemic transformation in mice and high expression is associated with poor patient outcomes in acute myeloid leukemia (AML) and T-acute lymphoblastic leukemia (T-ALL). Protein phosphorylation regulates the activity of many ETS factors but little is known about ERG in leukemic cells. To characterize ERG phosphorylation in leukemic cells, we applied liquid chromatography coupled tandem mass spectrometry and identified five phosphorylated serines on endogenous ERG in T-ALL and AML cells. S283 was distinct as it was abundantly phosphorylated in leukemic cells but not in healthy hematopoietic stem and progenitor cells (HSPCs). Overexpression of a phosphoactive mutant (S283D) increased expansion and clonogenicity of primary HSPCs over and above wild-type ERG. Using a custom antibody, we screened a panel of primary leukemic xenografts and showed that ERG S283 phosphorylation was mediated by mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) signaling and in turn regulated expression of components of this pathway. S283 phosphorylation facilitates ERG enrichment and transactivation at the ERG +85 HSPC enhancer that is active in AML and T-ALL with poor prognosis. Taken together, we have identified a specific post-translational modification in leukemic cells that promotes progenitor proliferation and is a potential target to modulate ERG-driven transcriptional programs in leukemia. PMID:27055868

  14. Forced expression of Hnf1b/Foxa3 promotes hepatic fate of embryonic stem cells.

    PubMed

    Yahoo, Neda; Pournasr, Behshad; Rostamzadeh, Jalal; Hakhamaneshi, Mohammad Saeed; Ebadifar, Asghar; Fathi, Fardin; Baharvand, Hossein

    2016-05-20

    Embryonic stem (ES) cell-derived hepatocytes have the potential to be used for basic research, regenerative medicine, and drug discovery. Recent reports demonstrated that in addition to conventional differentiation inducers such as chemical compounds and cytokines, overexpression of lineage-specific transcription factors could induce ES cells to differentiate to a hepatic fate. Here, we hypothesized that lentivirus-mediated inducible expression of hepatic lineage transcription factors could enhance mouse ES cells to hepatocyte-like cells. We screened the effects of candidate transcription factors Hnf1b, Hnf1a, Hnf4a, Foxa1, Foxa3 and Hex, and determined that the combination of Hnf1b/Foxa3 promoted expression of several hepatic lineage-specific markers and proteins, in addition to glycogen storage, ICG uptake, and secretion of albumin and urea. The differentiated cells were engraftable and expressed albumin when transplanted into a carbon tetrachloride-injured mouse model. These results demonstrated the crucial role of Hnf1b and Foxa3 in hepatogenesis in vitro and provided a valuable tool for the efficient differentiation of HLCs from ES cells. PMID:27107701

  15. Ethanol extract of Fructus Ligustri Lucidi promotes osteogenesis of mesenchymal stem cells.

    PubMed

    Li, Guo; Zhang, Xiao-ai; Zhang, Jin-fang; Chan, Chu-yan; Yew, David Tai Wai; He, Ming-liang; Lin, Marie Chia-mi; Leung, Ping-chung; Kung, Hsiang-fu

    2010-04-01

    Fructus Ligustri Lucidi (FLL) has been used in traditional Chinese medicine for over 1000 years. The ethanol extract of FLL (EFLL) has been shown to be a potential candidate in the prevention and treatment of osteoporosis. The present study aimed to determine whether EFLL carries out the effect by promoting osteogenesis in mesenchymal stem cells (MSCs). The osteogenic differentiation of MSCs was evaluated by their alkaline phosphatase (ALP) activities and mineralization. Expression of genes was detected by RT-PCR. We found that EFLL significantly stimulated the ALP activities and shortened the time needed for the mineralization of MSCs during osteogenic differentiation. The expression of several osteoblast differentiation regulators was also upregulated by EFLL during this process. Our study demonstrated that the EFLL is capable of enhancing osteogenic differentiation of MSCs. It might be useful for treating diseases with inadequate bone formation, including osteoporosis. PMID:19813230

  16. Transcriptome changes during TNF-α promoted osteogenic differentiation of dental pulp stem cells (DPSCs).

    PubMed

    Liu, Ya-Ke; Zhou, Zhen-Yu; Liu, Fan

    2016-08-01

    Dental pulp stem cells (DPSCs), due to the ease of isolation and their capacities of multi-lineage differentiation, are considered as attractive resources for regenerative medicine. In a previous study, we showed that TNF-α promoted the osteogenic differentiation of DPSCs via the NF-κB signaling pathway. However, the mechanisms of such differentiation were largely unknown. Here, we examined the gene expression profiles between undifferentiated, partially differentiated and fully differentiated DPSCs induced by TNF-α by performing the next-generation sequencing technique (RNA-Seq). Our results revealed a continuous transition of the transcriptome changes during TNF-α promoted osteogenic differentiation of DPSC. Bioinformatics analysis revealed a relatively general to specific transformation of the involved signaling pathways from the early to late stages of differentiation. Gene regulatory network analysis highlighted novel, key genes that are essential for osteogenic differentiation at different time points. These results were further validated by quantitative RT-PCR, confirming the high reliability of the RNA-Seq. Our data therefore will not only provide novel insights into the molecular mechanisms that drive the osteogenic differentiation of DPSCs, but also promote the studies of bone tissue engineering that utilizes DPSCs as a crucial resource. PMID:27237976

  17. Mohawk promotes the tenogenesis of mesenchymal stem cells through activation of the TGFβ signaling pathway.

    PubMed

    Liu, Huanhuan; Zhang, Can; Zhu, Shouan; Lu, Ping; Zhu, Ting; Gong, Xiaonan; Zhang, Ziwang; Hu, Jiajie; Yin, Zi; Heng, Boon Chin; Chen, Xiao; Ouyang, Hong Wei

    2015-02-01

    The transcription factor Mohawk (Mkx) is expressed in developing tendons and is an important regulator of tenogenic differentiation. However, the exact roles of Mkx in tendinopathy and tendon repair remain unclear. Using gene expression Omnibus datasets and immunofluorescence assays, we found that Mkx expression level was dramatically lower in human tendinopathy tissue and it is activated at specific stages of tendon development. In mesenchymal stem cells (MSCs), ectopic Mkx expression strikingly promoted tenogenesis more efficiently than Scleraxis (Scx), a well-known master transcription factor of tendon. Significantly higher levels of tenogenic gene expression and collagen fibril growth were observed with Mkx versus Scx. Interestingly, it was observed that Mkx dramatically upregulated Scx through binding to the Tgfb2 promoter. Additionally, the transplantation of Mkx-expressing-MSC sheets promoted tendon repair in a mouse model of Achilles-tendon defect. Taken together, these data shed light on previously unrecognized roles of Mkx in tendinopathy, tenogenesis, and tendon repair as well as in regulating the TGFβ pathway. PMID:25332192

  18. Exosomes secreted by mesenchymal stem cells promote endothelial cell angiogenesis by transferring miR-125a.

    PubMed

    Liang, Xiaolei; Zhang, Lina; Wang, Shihua; Han, Qin; Zhao, Robert Chunhua

    2016-06-01

    Angiogenesis plays crucial roles in various physiological processes including wound healing and tissue repair. It requires a tight interaction between endothelial cells and their surrounding environment. Mesenchymal stem cells (MSCs), one of the non-endothelial cell types present in the perivascular environment, have been shown to secret exosomes to modulate intercellular communications between MSCs and their target cells. In this study, we initially isolated exosomes secreted by human adipose-derived MSCs (adMSC-Exo) and examined their roles in angiogenesis. We found that adMSC-Exo could be taken up by endothelial cells and significantly promote angiogenesis in vitro and in vivo Further study showed that miR-125a was enriched in adMSC-Exo, and repressed the expression of the angiogenic inhibitor delta-like 4 (DLL4) by targeting its 3' untranslated region. Additionally, adMSC-Exo and its exosomal transferred miR-125a could repress DLL4 expression and modulate endothelial cell angiogenesis through promoting formation of endothelial tip cells. In conclusion, our study indicates that adMSC-Exo can transfer miR-125a to endothelial cells and promote angiogenesis by repressing DLL4. adMSC-Exo, as a pro-angiogenic factor, might be a promising candidate for therapeutical tissue repair. PMID:27252357

  19. Icariin promotes directed chondrogenic differentiation of bone marrow mesenchymal stem cells but not hypertrophy in vitro.

    PubMed

    Wang, Zhi Cong; Sun, Hui Jun; Li, Kai Hua; Fu, Chao; Liu, Mo Zhen

    2014-11-01

    Icariin (ICA), a Traditional Chinese Medicine, has been demonstrated to be a promoting compound for extracellular matrix synthesis and gene expression of chondrocytes. However, whether ICA can act as a substitute for or cooperate with growth factors to directly promote stable chondrogenesis of bone marrow mesenchymal stem cells (BMSCs) remains unknown. In the present study, rat BMSCs were cultivated in monolayer cultures with a chondrogenic medium containing transforming growth factor-β3 for 14 days; ICA was added to the same chondrogenic medium throughout the culture period at a concentration of 1×10(-6) M. Cell morphology was observed using an inverted microscope, and chondrogenic differentiation markers, including collagen II, aggrecan and SRY (sex determining region Y)-box 9 (SOX9), were detected by immunofluorescence, reverse transcription-quantitative polymerase chain reaction and western blot analysis. Hypertrophic differentiation was also analyzed using collagen I gene expression and alkaline phosphatase (ALP) activity. The results revealed that ICA was effective at forming an increased number of and larger aggregates, and significantly upregulated the mRNA expression levels and protein synthesis of collagen II, aggrecan and SOX9. Furthermore, the chondrogenic medium alone caused hypertrophic differentiation through the upregulation of collagen I gene expression and ALP activity, which was not potentiated by the presence of ICA. Thus, ICA promoted directed chondrogenic differentiation of BMSCs, but had no effect on hypertrophic differentiation. The present results also suggested that ICA may be an effective accelerant of growth factors for cartilage tissue engineering by promoting their chondrogenic differentiating effects but reducing the effect of hypertrophic differentiation. PMID:25289054

  20. Icariin promotes directed chondrogenic differentiation of bone marrow mesenchymal stem cells but not hypertrophy in vitro

    PubMed Central

    WANG, ZHI CONG; SUN, HUI JUN; LI, KAI HUA; FU, CHAO; LIU, MO ZHEN

    2014-01-01

    Icariin (ICA), a Traditional Chinese Medicine, has been demonstrated to be a promoting compound for extracellular matrix synthesis and gene expression of chondrocytes. However, whether ICA can act as a substitute for or cooperate with growth factors to directly promote stable chondrogenesis of bone marrow mesenchymal stem cells (BMSCs) remains unknown. In the present study, rat BMSCs were cultivated in monolayer cultures with a chondrogenic medium containing transforming growth factor-β3 for 14 days; ICA was added to the same chondrogenic medium throughout the culture period at a concentration of 1×10−6 M. Cell morphology was observed using an inverted microscope, and chondrogenic differentiation markers, including collagen II, aggrecan and SRY (sex determining region Y)-box 9 (SOX9), were detected by immunofluorescence, reverse transcription-quantitative polymerase chain reaction and western blot analysis. Hypertrophic differentiation was also analyzed using collagen I gene expression and alkaline phosphatase (ALP) activity. The results revealed that ICA was effective at forming an increased number of and larger aggregates, and significantly upregulated the mRNA expression levels and protein synthesis of collagen II, aggrecan and SOX9. Furthermore, the chondrogenic medium alone caused hypertrophic differentiation through the upregulation of collagen I gene expression and ALP activity, which was not potentiated by the presence of ICA. Thus, ICA promoted directed chondrogenic differentiation of BMSCs, but had no effect on hypertrophic differentiation. The present results also suggested that ICA may be an effective accelerant of growth factors for cartilage tissue engineering by promoting their chondrogenic differentiating effects but reducing the effect of hypertrophic differentiation. PMID:25289054

  1. Mesenchymal Stem Cells promote mammary cancer cell migration in vitro via the CXCR2 receptor

    PubMed Central

    Halpern, Jennifer L.; Kilbarger, Amy; Lynch, Conor C.

    2011-01-01

    Bone metastasis is a common event during breast cancer progression. Recently, mesenchymal stem cells (MSCs) have been implicated in the metastasis of primary mammary cancer. Given that bone is the native environment for MSCs, we hypothesized MSCs facilitate the homing of circulating mammary cancer cells to the bone. To test this hypothesis, we examined in vitro whether bone derived MSCs from FVB mice could influence the migration of syngeneic murine mammary cancer cell lines derived from the polyoma virus middle-T (PyMT) model of mammary gland tumorigenesis. Our data show that conditioned media derived from MSCs significantly enhanced the migration of PyMT mammary cancer cell lines. Analysis of conditioned media using a cytokine array revealed the presence of numerous cytokines in the MSC conditioned media, most notably, the murine orthologs of CXCL1 and CXCL5 that are cognate ligands of the CXCR2 receptor. Further investigation identified that; 1) CXCL1, CXCL5 and CXCR2 mRNA and protein were expressed by the MSCs and PyMT cell lines and; 2) neutralizing antibodies to CXCL1, CXCL5 and CXCR2 or a CXCR2 small molecule inhibitor (SB265610) significantly abrogated the migratory effect of the MSC conditioned media on the PyMT cells. Therefore, in vitro evidence demonstrates that bone derived MSCs play a role in the migration of mammary cancer cells, a conclusion that has potential implications for breast to bone metastasis in vivo. PMID:21601983

  2. The novel steroidal alkaloids dendrogenin A and B promote proliferation of adult neural stem cells

    SciTech Connect

    Khalifa, Shaden A.M.; Medina, Philippe de; Erlandsson, Anna; El-Seedi, Hesham R.; Silvente-Poirot, Sandrine; Poirot, Marc

    2014-04-11

    Highlights: • Dendrogenin A and B are new aminoalkyl oxysterols. • Dendrogenins stimulated neural stem cells proliferation. • Dendrogenins induce neuronal outgrowth from neurospheres. • Dendrogenins provide new therapeutic options for neurodegenerative disorders. - Abstract: Dendrogenin A (DDA) and dendrogenin B (DDB) are new aminoalkyl oxysterols which display re-differentiation of tumor cells of neuronal origin at nanomolar concentrations. We analyzed the influence of dendrogenins on adult mice neural stem cell proliferation, sphere formation and differentiation. DDA and DDB were found to have potent proliferative effects in neural stem cells. Additionally, they induce neuronal outgrowth from neurospheres during in vitro cultivation. Taken together, our results demonstrate a novel role for dendrogenins A and B in neural stem cell proliferation and differentiation which further increases their likely importance to compensate for neuronal cell loss in the brain.

  3. PTHrP in differentiating human mesenchymal stem cells: transcript isoform expression, promoter methylation, and protein accumulation.

    PubMed

    Longo, Alessandra; Librizzi, Mariangela; Naselli, Flores; Caradonna, Fabio; Tobiasch, Edda; Luparello, Claudio

    2013-10-01

    Human PTHrP gene displays a complex organization with nine exons producing diverse mRNA variants due to alternative splicing at 5' and 3' ends and the existence of three different transcriptional promoters (P1, P2 and P3), two of which (P2 and P3) contain CpG islands. It is known that the expression of PTHrP isoforms may be differentially regulated in a developmental stage- and tissue-specific manner. To search for novel molecular markers of stemness/differentiation, here we have examined isoform expression in fat-derived mesenchymal stem cells both maintained in stem conditions and induced toward adipo- and osteogenesis. In addition, the expression of the splicing isoforms derived from P2 and P3 promoters was correlated to the state of methylation of the latter. Moreover, we also performed a quantitative evaluation of intracellular and secreted PTHrP protein product in undifferentiated stem cells and in parallel cultures at various differentiation stages. The data obtained indicate that from the stemness condition to that of osteo- and adipo-genic differentiated cells, the expression of isoforms becomes increasingly selective, thereby being a potential gene signature for the monitoring of cell stem or committed/differentiating state and that the switching-off of PTHrP isoform expression is mostly promoter methylation-dependent. Moreover, PTHrP intracellular retention is down-regulated in osteo-differentiating cells whereas the secretion of the protein in the extracellular medium is up-regulated with respect to stem cells, thereby suggesting that these variations of the intracellular and extracellular levels of PTHrP could potentially be enclosed in the list of the available protein signature of osteogenic differentiation. PMID:23810909

  4. Stem Cells on Biomaterials for Synthetic Grafts to Promote Vascular Healing

    PubMed Central

    Babczyk, Patrick; Conzendorf, Clelia; Klose, Jens; Schulze, Margit; Harre, Kathrin; Tobiasch, Edda

    2014-01-01

    This review is divided into two interconnected parts, namely a biological and a chemical one. The focus of the first part is on the biological background for constructing tissue-engineered vascular grafts to promote vascular healing. Various cell types, such as embryonic, mesenchymal and induced pluripotent stem cells, progenitor cells and endothelial- and smooth muscle cells will be discussed with respect to their specific markers. The in vitro and in vivo models and their potential to treat vascular diseases are also introduced. The chemical part focuses on strategies using either artificial or natural polymers for scaffold fabrication, including decellularized cardiovascular tissue. An overview will be given on scaffold fabrication including conventional methods and nanotechnologies. Special attention is given to 3D network formation via different chemical and physical cross-linking methods. In particular, electron beam treatment is introduced as a method to combine 3D network formation and surface modification. The review includes recently published scientific data and patents which have been registered within the last decade. PMID:26237251

  5. PERK Limits Drosophila Lifespan by Promoting Intestinal Stem Cell Proliferation in Response to ER Stress.

    PubMed

    Wang, Lifen; Ryoo, Hyung Don; Qi, Yanyan; Jasper, Heinrich

    2015-05-01

    Intestinal homeostasis requires precise control of intestinal stem cell (ISC) proliferation. In Drosophila, this control declines with age largely due to chronic activation of stress signaling and associated chronic inflammatory conditions. An important contributor to this condition is the age-associated increase in endoplasmic reticulum (ER) stress. Here we show that the PKR-like ER kinase (PERK) integrates both cell-autonomous and non-autonomous ER stress stimuli to induce ISC proliferation. In addition to responding to cell-intrinsic ER stress, PERK is also specifically activated in ISCs by JAK/Stat signaling in response to ER stress in neighboring cells. The activation of PERK is required for homeostatic regeneration, as well as for acute regenerative responses, yet the chronic engagement of this response becomes deleterious in aging flies. Accordingly, knocking down PERK in ISCs is sufficient to promote intestinal homeostasis and extend lifespan. Our studies highlight the significance of the PERK branch of the unfolded protein response of the ER (UPRER) in intestinal homeostasis and provide a viable strategy to improve organismal health- and lifespan. PMID:25945494

  6. Hierarchical Micro-Nano Surface Topography Promotes Long-Term Maintenance of Undifferentiated Mouse Embryonic Stem Cells.

    PubMed

    Jaggy, Mona; Zhang, Ping; Greiner, Alexandra M; Autenrieth, Tatjana J; Nedashkivska, Victoria; Efremov, Alexander N; Blattner, Christine; Bastmeyer, Martin; Levkin, Pavel A

    2015-10-14

    Understanding of stem cell-surface interactions and, in particular, long-term maintenance of stem cell pluripotency on well-defined synthetic surfaces is crucial for fundamental research and biomedical applications of stem cells. Here, we show that synthetic surfaces possessing hierarchical micro-nano roughness (MN-surfaces) promote long-term self-renewal (>3 weeks) of mouse embryonic stem cells (mESCs) as monitored by the expression levels of the pluripotency markers octamer-binding transcription factor 4 (Oct4), Nanog, and alkaline phosphatase. On the contrary, culturing of mESCs on either smooth (S-) or nanorough polymer surfaces (N-surfaces) leads to their fast differentiation. Moreover, we show that regular passaging of mESCs on the hierarchical MN-polymer surface leads to an increased homogeneity and percentage of Oct4-positive stem cell colonies as compared to mESCs grown on fibroblast feeder cells. Immunostaining revealed the absence of focal adhesion markers on all polymer substrates studied. However, only the MN-surfaces elicited the formation of actin-positive cell protrusions, indicating an alternative anchorage mechanism involved in the maintenance of mESC stemness. PMID:26351257

  7. Drug-based modulation of endogenous stem cells promotes functional remyelination in vivo

    PubMed Central

    Najm, Fadi J.; Madhavan, Mayur; Zaremba, Anita; Shick, Elizabeth; Karl, Robert T.; Factor, Daniel C.; Miller, Tyler E.; Nevin, Zachary S.; Kantor, Christopher; Sargent, Alex; Quick, Kevin L.; Schlatzer, Daniela M.; Tang, Hong; Papoian, Ruben; Brimacombe, Kyle R.; Shen, Min; Boxer, Matthew B.; Jadhav, Ajit; Robinson, Andrew P.; Podojil, Joseph R.; Miller, Stephen D.; Miller, Robert H.; Tesar, Paul J.

    2015-01-01

    Multiple sclerosis (MS) involves an aberrant autoimmune response and progressive failure of remyelination in the central nervous system (CNS). Prevention of neural degeneration and subsequent disability requires remyelination through the generation of new oligodendrocytes, but current treatments exclusively target the immune system. Oligodendrocyte progenitor cells (OPCs) are stem cells in the CNS and the principal source of myelinating oligodendrocytes1. OPCs are abundant in demyelinated regions of MS patients, yet fail to differentiate, thereby representing a cellular target for pharmacological intervention2. To discover therapeutic compounds for enhancing myelination from endogenous OPCs, we screened a library of bioactive small molecules on mouse pluripotent epiblast stem cell (EpiSC)-derived OPCs3–5. We identified seven drugs that functioned at nanomolar doses to selectively enhance the generation of mature oligodendrocytes from OPCs in vitro. Two drugs, miconazole and clobetasol, were effective in promoting precocious myelination in organotypic cerebellar slice cultures, and in vivo in early postnatal mouse pups. Systemic delivery of each of the two drugs significantly increased the number of new oligodendrocytes and enhanced remyelination in a lysolecithin-induced mouse model of focal demyelination. Administering each of the two drugs at the peak of disease in the experimental autoimmune encephalomyelitis (EAE) mouse model of chronic progressive MS resulted in striking reversal of disease severity. Immune response assays showed that miconazole functioned directly as a remyelinating drug with no effect on the immune system, whereas clobetasol was a potent immunosuppressant as well as a remyelinating agent. Mechanistic studies showed that miconazole and clobetasol functioned in OPCs through mitogen-activated protein kinase (MAPK) and glucocorticoid receptor (GR) signaling, respectively. Furthermore, both drugs enhanced the generation of human

  8. COX-2 Promotes Migration and Invasion by the Side Population of Cancer Stem Cell-Like Hepatocellular Carcinoma Cells

    PubMed Central

    Guo, Zhe; Jiang, Jing-Hang; Zhang, Jun; Yang, Hao-Jie; Yang, Fu-Quan; Qi, Ya-Peng; Zhong, Yan-Ping; Su, Jie; Yang, Ri-Rong; Li, Le-Qun; Xiang, Bang-De

    2015-01-01

    Abstract Cancer stem cells (CSCs) are thought to be responsible for tumor relapse and metastasis due to their abilities to self-renew, differentiate, and give rise to new tumors. Cyclooxygenase-2 (COX-2) is highly expressed in several kinds of CSCs, and it helps promote stem cell renewal, proliferation, and radioresistance. Whether and how COX-2 contributes to CSC migration and invasion is unclear. In this study, COX-2 was overexpressed in the CSC-like side population (SP) of the human hepatocellular carcinoma (HCC) cell line HCCLM3. COX-2 overexpression significantly enhanced migration and invasion of SP cells, while reducing expression of metastasis-related proteins PDCD4 and PTEN. Treating SP cells with the selective COX-2 inhibitor celecoxib down-regulated COX-2 and caused a dose-dependent reduction in cell migration and invasion, which was associated with up-regulation of PDCD4 and PTEN. These results suggest that COX-2 exerts pro-metastatic effects on SP cells, and that these effects are mediated at least partly through regulation of PDCD4 and PTEN expression. These results further suggest that celecoxib may be a promising anti-metastatic agent to reduce migration and invasion by hepatic CSCs. PMID:26554780

  9. Umbilical cord-derived mesenchymal stem cells inhibit growth and promote apoptosis of HepG2 cells.

    PubMed

    Tang, Ying-Mei; Bao, Wei-Min; Yang, Jin-Hui; Ma, Lin-Kun; Yang, Jing; Xu, Ying; Yang, Li-Hong; Sha, Feng; Xu, Zhi-Yuan; Wu, Hua-Mei; Zhou, Wei; Li, Yan; Li, Yu-Hua

    2016-09-01

    Hepatocellular carcinoma is the fifth most common type of cancer worldwide and remains difficult to treat. The aim of this study was to investigate the effects of mesenchymal stem cells (MSCs) derived from the umbilical cord (UC‑MSCs) on HepG2 hepatocellular carcinoma cells. UC‑MSCs were co‑cultured with HepG2 cells and biomarkers of UC‑MSCs were analyzed by flow cytometry. mRNA and protein expression of genes were determined by reverse transcription‑polymerase chain reaction and flow cytometry, respectively. Passage three and seven UC‑MSCs expressed CD29, CD44, CD90 and CD105, whereas CD34 and CD45 were absent on these cells. Co‑culture with UC‑MSCs inhibited proliferation and promoted apoptosis of HepG2 cells in a time‑dependent manner. The initial seeding density of UC‑MSCs also influenced the proliferation and apoptosis of HepG2 cells, with an increased number of UC‑MSCs causing enhanced proliferation inhibition and cell apoptosis. Co‑culture with UC‑MSCs downregulated mRNA and protein expression of α‑fetoprotein (AFP), Bcl‑2 and Survivin in HepG2 cells. Thus, UC‑MSCs may inhibit growth and promote apoptosis of HepG2 cells through downregulation of AFP, Bcl‑2 and Survivin. US-MSCs may be used as a novel therapy for treating hepatocellular carcinoma in the future. PMID:27485485

  10. Inhibition of Sirt1 promotes neural progenitors toward motoneuron differentiation from human embryonic stem cells

    SciTech Connect

    Zhang, Yun; Wang, Jing; Chen, Guian; Fan, Dongsheng; Deng, Min

    2011-01-14

    Research highlights: {yields} Nicotinamide inhibit Sirt1. {yields} MASH1 and Ngn2 activation. {yields} Increase the expression of HB9. {yields} Motoneurons formation increases significantly. -- Abstract: Several protocols direct human embryonic stem cells (hESCs) toward differentiation into functional motoneurons, but the efficiency of motoneuron generation varies based on the human ESC line used. We aimed to develop a novel protocol to increase the formation of motoneurons from human ESCs. In this study, we tested a nuclear histone deacetylase protein, Sirt1, to promote neural precursor cell (NPC) development during differentiation of human ESCs into motoneurons. A specific inhibitor of Sirt1, nicotinamide, dramatically increased motoneuron formation. We found that about 60% of the cells from the total NPCs expressed HB9 and {beta}III-tubulin, commonly used motoneuronal markers found in neurons derived from ESCs following nicotinamide treatment. Motoneurons derived from ESC expressed choline acetyltransferase (ChAT), a positive marker of mature motoneuron. Moreover, we also examined the transcript levels of Mash1, Ngn2, and HB9 mRNA in the differentiated NPCs treated with the Sirt1 activator resveratrol (50 {mu}M) or inhibitor nicotinamide (100 {mu}M). The levels of Mash1, Ngn2, and HB9 mRNA were significantly increased after nicotinamide treatment compared with control groups, which used the traditional protocol. These results suggested that increasing Mash1 and Ngn2 levels by inhibiting Sirt1 could elevate HB9 expression, which promotes motoneuron differentiation. This study provides an alternative method for the production of transplantable motoneurons, a key requirement in the development of hESC-based cell therapy in motoneuron disease.

  11. Kuwanon V Inhibits Proliferation, Promotes Cell Survival and Increases Neurogenesis of Neural Stem Cells

    PubMed Central

    Kong, Sun-Young; Park, Min-Hye; Lee, Mina; Kim, Jae-Ouk; Lee, Ha-Rim; Han, Byung Woo; Svendsen, Clive N.; Sung, Sang Hyun; Kim, Hyun-Jung

    2015-01-01

    Neural stem cells (NSCs) have the ability to proliferate and differentiate into neurons and glia. Regulation of NSC fate by small molecules is important for the generation of a certain type of cell. The identification of small molecules that can induce new neurons from NSCs could facilitate regenerative medicine and drug development for neurodegenerative diseases. In this study, we screened natural compounds to identify molecules that are effective on NSC cell fate determination. We found that Kuwanon V (KWV), which was isolated from the mulberry tree (Morus bombycis) root, increased neurogenesis in rat NSCs. In addition, during NSC differentiation, KWV increased cell survival and inhibited cell proliferation as shown by 5-bromo-2-deoxyuridine pulse experiments, Ki67 immunostaining and neurosphere forming assays. Interestingly, KWV enhanced neuronal differentiation and decreased NSC proliferation even in the presence of mitogens such as epidermal growth factor and fibroblast growth factor 2. KWV treatment of NSCs reduced the phosphorylation of extracellular signal-regulated kinase 1/2, increased mRNA expression levels of the cyclin-dependent kinase inhibitor p21, down-regulated Notch/Hairy expression levels and up-regulated microRNA miR-9, miR-29a and miR-181a. Taken together, our data suggest that KWV modulates NSC fate to induce neurogenesis, and it may be considered as a new drug candidate that can regenerate or protect neurons in neurodegenerative diseases. PMID:25706719

  12. Transdifferentiation-Induced Neural Stem Cells Promote Recovery of Middle Cerebral Artery Stroke Rats

    PubMed Central

    Ma, Jianhua; Zhang, Maoying; Li, Shaowu; Wu, Bingshan; Nie, Xiaohu; Jiao, Jiao; Zhao, Hao; Wang, Shanshan; Yang, Yuanyuan; Zhang, Yesen; Sun, Yilin; Wicha, Max S.; Chang, Alfred E.; Gao, Shaorong; Li, Qiao; Xu, Ruxiang

    2015-01-01

    Induced neural stem cells (iNSCs) can be directly transdifferentiated from somatic cells. One potential clinical application of the iNSCs is for nerve regeneration. However, it is unknown whether iNSCs function in disease models. We produced transdifferentiated iNSCs by conditional overexpressing Oct4, Sox2, Klf4, c-Mycin mouse embryonic fibroblasts. They expanded readily in vitro and expressed NSC mRNA profile and protein markers. These iNSCs differentiated into mature astrocytes, neurons and oligodendrocytes in vitro. Importantly, they reduced lesion size, promoted the recovery of motor and sensory function as well as metabolism status in middle cerebral artery stroke rats. These iNSCs secreted nerve growth factors, which was associated with observed protection of neurons from apoptosis. Furthermore, iNSCs migrated to and passed through the lesion in the cerebral cortex, where Tuj1+ neurons were detected. These findings have revealed the function of transdifferentiated iNSCs in vivo, and thus provide experimental evidence to support the development of personalized regenerative therapy for CNS diseases by using genetically engineered autologous somatic cells. PMID:26352672

  13. The Rab2A GTPase Promotes Breast Cancer Stem Cells and Tumorigenesis via Erk Signaling Activation

    PubMed Central

    Luo, Man-Li; Gong, Chang; Chen, Chun-Hau; Hu, Hai; Huang, Pengyu; Zheng, Min; Yao, Yandan; Wei, Shuo; Wulf, Gerburg; Lieberman, Judy; Zhou, Xiao Zhen; Song, Erwei; Lu, Kun Ping

    2015-01-01

    SUMMARY Proline-directed phosphorylation is regulated by the prolyl isomerase Pin1, which plays a fundamental role in driving breast cancer stem-like cells (BCSCs). Rab2A is a small GTPase critical for vesicle trafficking. Here, we show that Pin1 increases Rab2A transcription to promote BCSC expansion and tumorigenesis in vitro and in vivo. Mechanistically, Rab2A directly interacts with and prevents dephosphorylation/inactivation of Erk1/2 by the MKP3 phosphatase, resulting in Zeb1 upregulation and β-catenin nuclear translocation. In cancer cells, Rab2A is activated via gene amplification, mutation or Pin1 overexpression. Rab2A overexpression or mutation endows BCSC traits to primary normal human breast epithelial cells, whereas silencing Rab2A potently inhibits the expansion and tumorigenesis of freshly isolated BCSCs. Finally, Rab2A overexpression correlates with poor clinical outcome in breast cancer patients. Thus, Pin1/Rab2A/Erk drives BCSC expansion and tumorigenicity, suggesting potential drug targets. PMID:25818297

  14. Synthesis of Eupalinilide E, a Promoter of Human Hematopoietic Stem and Progenitor Cell Expansion.

    PubMed

    Johnson, Trevor C; Chin, Matthew R; Han, Tianxu; Shen, John Paul; Rana, Tariq; Siegel, Dionicio

    2016-05-11

    Improving the ex vivo and in vivo production of hematopoietic stem and progenitor cells (HSPCs) has the potential to address the short supply of these cells that are used in the treatment of various blood diseases and disorders. Eupalinilide E promotes the expansion of human HSPCs and inhibits subsequent differentiation, leading to increased numbers of clinically useful cells. This natural product represents an important tool to uncover new methods to drive expansion while inhibiting differentiation. However, in the process of examining these effects, which occur through a novel mechanism, the natural product was consumed, which limited additional investigation. To provide renewed and improved access to eupalinilide E, a laboratory synthesis has been developed and is reported herein. The synthetic route can access >400 mg in a single batch, employing reactions conducted on useful scales in a single vessel. Key transformations enabling the approach include a diastereoselective borylative enyne cyclization and a late-stage double allylic C-H oxidation as well as adapted Luche reduction and aluminum-mediated epoxidation reactions to maximize the synthetic efficiency. Retesting of the synthetic eupalinilide E confirmed the compound's ability to expand HSPCs and inhibit differentiation. PMID:27096704

  15. Stromal cell-derived factor-1 promotes human adipose tissue-derived stem cell survival and chronic wound healing

    PubMed Central

    LI, QIANG; GUO, YANPING; CHEN, FEIFEI; LIU, JING; JIN, PEISHENG

    2016-01-01

    Adipose tissue-derived stem cells (ADSCs) hold great potential for the stem cell-based therapy of cutaneous wound healing. Stromal cell-derived factor-1 (SDF-1) activates CXC chemokine receptor (CXCR)4+ and CXCR7+ cells and plays an important role in wound healing. Increasing evidence suggests a critical role for SDF-1 in cell apoptosis and the survival of mesenchymal stem cells. However, the function of SDF-1 in the apoptosis and wound healing ability of ADSCs is not well understood. The aim of this study was to analyze the effect of SDF-1 on the apoptosis and therapeutic effect of ADSCs in cutaneous chronic wounds in vitro and in vivos. By flow cytometric analysis, it was found that hypoxia and serum free promoted the apoptosis of ADSCs. When pretreated with SDF-1, the apoptosis of ADSCs induced by hypoxia and serum depletion was partly recovered. Furthermore, in vivo experiments established that the post-implantation cell survival and chronic wound healing ability of ADSCs were increased following pretreatment with SDF-1 in a diabetic mouse model of chronic wound healing. To explore the potential mechanism underlying the effect of SDF-1 on ADSC apoptosis, western blot analysis was employed and the results indicate that SDF-1 may protect against cell apoptosis in hypoxic and serum-free conditions through activation of the caspase signaling pathway in ADSCs. This study provides evidence that SDF-1 pretreatment can increase the therapeutic effect of ADSCs in cutaneous chronic wounds in vitro and in vivo. PMID:27347016

  16. Mesenchymal stem cell therapy promotes the improvement and recovery of renal function in a preclinical model.

    PubMed

    Urt, Antônio Filho; Oliveira, Rodrigo Juliano; Hermeto, Larissa Correa; Pesarini, João Renato; David, Natan de; Cantero, Wilson de Barros; Falcão, Gustavo; Marks, Guido; Antoniolli-Silva, Andréia Conceição Milan Brochado

    2016-06-01

    Acute renal failure (ARF) is an extremely important public health issue in need of novel therapies. The present study aimed to evaluate the capacity of mesenchymal stem cell (MSC) therapy to promote the improvement and recovery of renal function in a preclinical model. Wistar rats were used as the experimental model, and our results show that cisplatin (5mg/kg) can efficiently induce ARF, as measured by changes in biochemical (urea and creatinine) and histological parameters. MSC therapy performed 24h after the administration of chemotherapy resulted in normalized plasma urea and creatinine levels 30 and 45d after the onset of kidney disease. Furthermore, MSC therapy significantly reduced histological changes (intratubular cast formation in protein overload nephropathy and tubular hydropic degeneration) in this ARF model. Thus, considering that current therapies for ARF are merely palliative and that MSC therapy can promote the improvement and recovery of renal function in this model system, we suggest that innovative/alternative therapies involving MSCs should be considered for clinical studies in humans to treat ARF. PMID:27275667

  17. Bone marrow mesenchymal stem cells transplantation promotes the release of endogenous erythropoietin after ischemic stroke

    PubMed Central

    Lv, Wen; Li, Wen-yu; Xu, Xiao-yan; Jiang, Hong; Bang, Oh Yong

    2015-01-01

    This study investigated whether bone marrow mesenchymal stem cell (BMSC) transplantation protected ischemic cerebral injury by stimulating endogenous erythropoietin. The model of ischemic stroke was established in rats through transient middle cerebral artery occlusion. Twenty-four hours later, 1 × 106 human BMSCs (hBMSCs) were injected into the tail vein. Fourteen days later, we found that hBMSCs promoted the release of endogenous erythropoietin in the ischemic region of rats. Simultaneously, 3 μg/d soluble erythropoietin receptor (sEPOR) was injected into the lateral ventricle, and on the next 13 consecutive days. sEPOR blocked the release of endogenous erythropoietin. The neurogenesis in the subventricular zone was less in the hBMSCs + sEPOR group than in the hBMSCs + heat-denatured sEPOR group. The adhesive-removal test result and the modified Neurological Severity Scores (mNSS) were lower in the hBMSCs + sEPOR group than in the heat-denatured sEPOR group. The adhesive-removal test result and mNSS were similar between the hBMSCs + heat-denatured sEPOR group and the hBMSCs + sEPOR group. These findings confirm that BMSCs contribute to neurogenesis and improve neurological function by promoting the release of endogenous erythropoietin following ischemic stroke. PMID:26487854

  18. Mesenchymal stem cell therapy promotes the improvement and recovery of renal function in a preclinical model

    PubMed Central

    Urt-Filho, Antônio; Oliveira, Rodrigo Juliano; Hermeto, Larissa Correa; Pesarini, João Renato; de David, Natan; Cantero, Wilson de Barros; Falcão, Gustavo; Marks, Guido; Antoniolli-Silva, Andréia Conceição Milan Brochado

    2016-01-01

    Abstract Acute renal failure (ARF) is an extremely important public health issue in need of novel therapies. The present study aimed to evaluate the capacity of mesenchymal stem cell (MSC) therapy to promote the improvement and recovery of renal function in a preclinical model. Wistar rats were used as the experimental model, and our results show that cisplatin (5mg/kg) can efficiently induce ARF, as measured by changes in biochemical (urea and creatinine) and histological parameters. MSC therapy performed 24h after the administration of chemotherapy resulted in normalized plasma urea and creatinine levels 30 and 45d after the onset of kidney disease. Furthermore, MSC therapy significantly reduced histological changes (intratubular cast formation in protein overload nephropathy and tubular hydropic degeneration) in this ARF model. Thus, considering that current therapies for ARF are merely palliative and that MSC therapy can promote the improvement and recovery of renal function in this model system, we suggest that innovative/alternative therapies involving MSCs should be considered for clinical studies in humans to treat ARF. PMID:27275667

  19. Production of interleukin-4 in CD133+ cervical cancer stem cells promotes resistance to apoptosis and initiates tumor growth

    PubMed Central

    LIU, CHUN-TAO; XIN, YING; TONG, CHUN-YAN; LI, BING; BAO, HONG-LI; ZHANG, CAI-YUN; WANG, XUE-HUI

    2016-01-01

    The cancer stem cell (CSC) theory suggests that cancer growth and invasion is dictated by the small population of CSCs within the heterogenous tumor. The aim of the present study was to elucidate the cause for chemotherapy failure and the resistance of CSCs to apoptosis. A total of ~2.3% cluster of differentiation (CD)133+ cancer stem-like side population (SP) cells were identified in cases of uterine cervical cancer. These CD133+ SP cells were found to potently initiate tumor growth and invasion, as they exhibit transcriptional upregulation of stemness genes, including octamer-binding transcription factor-4, B-cell-specific Moloney murine leukemia virus insertion site-1, epithelial cell adhesion molecule, (sex determining region Y)-box 2, Nestin and anti-apoptotic B cell lymphoma-2. In addition, the CD133+ SP cells showed resistance to multi-drug treatment and apoptosis. The present study further showed that the secretion of interleukin-4 (IL-4) in CD133+ cervical cancer SP cells promoted cell proliferation and prevented the SP cells from apoptosis. Following the neutralization of IL-4 with anti-IL-4 antibody, the CD133+ SP cells were more sensitive to drug treatment and apoptosis. Therefore, the data obtained in the present study suggested that the autocrine secretion of IL-4 promotes increased survival and resistance to cell death in CSCs. PMID:27121303

  20. Combinatorial Fibronectin and Laminin Signaling Promote Highly Efficient Cardiac Differentiation of Human Embryonic Stem Cells

    PubMed Central

    Sa, Silin; Wong, Lian

    2014-01-01

    Abstract Cardiomyocytes (CMs) differentiated from human embryonic stem cells (hESCs) are a promising and potentially unlimited cell source for myocardial repair and regeneration. Recently, multiple methodologies—primarily based on the optimization of growth factors—have been described for efficient cardiac differentiation of hESCs. However, the role of extracellular matrix (ECM) signaling in CM differentiation has not yet been explored fully. This study examined the role of ECM signaling in the efficient generation of CMs from both H7 and H9 ESCs. The hESCs were differentiated on ECM substrates composed of a range of fibronectin (FN) and laminin (LN) ratios and gelatin and evaluated by the fluorescence activated cell scanning (FACS) analysis on day 14. Of the ECM substrates examined, the 70:30 FN:LN reproducibly generated the greatest numbers of CMs from both hESC lines. Moreover, the LN receptor integrin β4 (ITGB4) and FN receptor integrin β5 (ITGB5) genes, jointly with increased phosphorylated focal adhension kinase and phosphorylated extracellular signal-regulated kinases (p-ERKs), were up-regulated over 13-fold in H7 and H9 cultured on 70:30 FN:LN compared with gelatin. Blocking studies confirmed the role of all these molecules in CM specification, suggesting that the 70:30 FN:LN ECM promotes highly efficient differentiation of CMs through the integrin-mediated MEK/ERK signaling pathway. Lastly, the data suggest that FN:LN-induced signaling utilizes direct cell-to-cell signaling from distinct ITGB4+ and ITGB5+ cells. PMID:25126479

  1. NR2F2 regulates bone marrow-derived mesenchymal stem cell-promoted proliferation of Reh cells.

    PubMed

    Zhu, Ni; Wang, Huafang; Wei, Jieping; Wang, Binsheng; Shan, Wei; Lai, Xiaoyu; Zhao, Yanmin; Yu, Jian; Huang, He

    2016-08-01

    Bone marrow-derived mesenchymal stem cells (BM-MSCs) are pivotal components of the leukemic microenvironment. BM-MSCs have been previously reported to promote the proliferation of leukemic cells. To further understand the molecular mechanisms of BM-MSC-induced proliferation of leukemic cells, the present study co-cultured acute lymphoblastic leukemia (ALL) Reh cells with BM-MSCs. The current study used methods including shRNA, flow cytometry, MTT, reverse transcription-quantitative polymerase chain reaction, ELISA and western blotting. The data of the present study demonstrated that BM‑MSCs promote the proliferation of Reh cells and the NR2F2 mRNA and protein levels were elevated in BM‑MSCs following co‑culture. Additionally, it was demonstrated that shRNA knockdown of NR2F2 inhibited BM‑MSC‑induced proliferation of Reh cells. Furthermore, following downregulation of NR2F2, vascular endothelial growth factor A (VEGFA) secretion by BM‑MSCs was reduced. The present study demonstrated that NR2F2 mediates BM‑MSC‑induced proliferation of Reh cells, partially via regulation of VEGFA. Disrupting microenvironmental support by targeting NR2F2 may be a potential therapeutic strategy for ALL. PMID:27314877

  2. Reiterated Targeting Peptides on the Nanoparticle Surface Significantly Promote Targeted Vascular Endothelial Growth Factor Gene Delivery to Stem Cells.

    PubMed

    Wang, Dong-Dong; Yang, Mingying; Zhu, Ye; Mao, Chuanbin

    2015-12-14

    Nonviral gene delivery vectors hold great promise for gene therapy due to the safety concerns with viral vectors. However, the application of nonviral vectors is hindered by their low transfection efficiency. Herein, in order to tackle this challenge, we developed a nonviral vector integrating lipids, sleeping beauty transposon system and 8-mer stem cell targeting peptides for safe and efficient gene delivery to hard-to-transfect mesenchymal stem cells (MSCs). The 8-mer MSC-targeting peptides, when synthetically reiterated in three folds and chemically presented on the surface, significantly promoted the resultant lipid-based nanoparticles (LBNs) to deliver VEGF gene into MSCs with a high transfection efficiency (∼52%) and long-lasting gene expression (for longer than 170 h) when compared to nonreiterated peptides. However, the reiterated stem cell targeting peptides do not enable the highly efficient gene transfer to other control cells. This work suggests that the surface presentation of the reiterated stem cell-targeting peptides on the nonviral vectors is a promising method for improving the efficiency of cell-specific nonviral gene transfection in stem cells. PMID:26588028

  3. Nitric oxide promotes epidermal stem cell migration via cGMP-Rho GTPase signalling

    PubMed Central

    Zhan, Rixing; He, Weifeng; Wang, Fan; Yao, Zhihui; Tan, Jianglin; Xu, Rui; Zhou, Junyi; Wang, Yuzhen; Li, Haisheng; Wu, Jun; LUO, Gaoxing

    2016-01-01

    The migration and reepithelization of epidermal stem cells (ESCs) are the most critical processes in wound healing. The gaseous messenger nitric oxide (NO) has multiple biological effects, but its actions on ESCs are poorly understood. In this study, an NO donor, S-nitroso-N-acetylpenicillamine (SNAP), was found to facilitate the in vitro migration of human ESCs (huESCs) in both live-imaging and scratch models. In addition, pull-down assays demonstrated that SNAP could activate the small GTPases RhoA and Rac1 of the Rho family, but not Cdc42. Moreover, the effects of SNAP on the migration and F-actin polymerization of ESCs could be blocked by inhibitors of cGMP, PKG, RhoA or Rac1, and by a specific siRNA of RhoA or Rac1, but not by a Cdc42 inhibitor or siRNA. Furthermore, the roles of NO in ESC migration via cGMP-Rho GTPase signalling in vivo were confirmed by tracing 5-bromo-2-deoxyuridine (BrdU)-labelled cells in a superficial, partial-thickness scald mouse model. Thus, the present study demonstrated that the NO donor SNAP could promote huESC migration in vitro. Furthermore, NO was found to induce ESC migration via cGMP-Rho GTPase RhoA and Rac1 signalling, but not Cdc42 signalling, both in vivo and in vitro. PMID:27469024

  4. TGF-beta signalling in the adult neurogenic niche promotes stem cell quiescence as well as generation of new neurons

    PubMed Central

    Kandasamy, Mahesh; Lehner, Bernadette; Kraus, Sabrina; Sander, Paul Ramm; Marschallinger, Julia; Rivera, Francisco J; Trümbach, Dietrich; Ueberham, Uwe; Reitsamer, Herbert A; Strauss, Olaf; Bogdahn, Ulrich; Couillard-Despres, Sebastien; Aigner, Ludwig

    2014-01-01

    Members of the transforming growth factor (TGF)-β family govern a wide range of mechanisms in brain development and in the adult, in particular neuronal/glial differentiation and survival, but also cell cycle regulation and neural stem cell maintenance. This clearly created some discrepancies in the field with some studies favouring neuronal differentiation/survival of progenitors and others favouring cell cycle exit and neural stem cell quiescence/maintenance. Here, we provide a unifying hypothesis claiming that through its regulation of neural progenitor cell (NPC) proliferation, TGF-β signalling might be responsible for (i) maintaining stem cells in a quiescent stage, and (ii) promoting survival of newly generated neurons and their functional differentiation. Therefore, we performed a detailed histological analysis of TGF-β1 signalling in the hippocampal neural stem cell niche of a transgenic mouse that was previously generated to express TGF-β1 under a tetracycline regulatable Ca-Calmodulin kinase promoter. We also analysed NPC proliferation, quiescence, neuronal survival and differentiation in relation to elevated levels of TGF-β1 in vitro and in vivo conditions. Finally, we performed a gene expression profiling to identify the targets of TGF-β1 signalling in adult NPCs. The results demonstrate that TGF-β1 promotes stem cell quiescence on one side, but also neuronal survival on the other side. Thus, considering the elevated levels of TGF-β1 in ageing and neurodegenerative diseases, TGF-β1 signalling presents a molecular target for future interventions in such conditions. PMID:24779367

  5. TGF-beta signalling in the adult neurogenic niche promotes stem cell quiescence as well as generation of new neurons.

    PubMed

    Kandasamy, Mahesh; Lehner, Bernadette; Kraus, Sabrina; Sander, Paul Ramm; Marschallinger, Julia; Rivera, Francisco J; Trümbach, Dietrich; Ueberham, Uwe; Reitsamer, Herbert A; Strauss, Olaf; Bogdahn, Ulrich; Couillard-Despres, Sebastien; Aigner, Ludwig

    2014-07-01

    Members of the transforming growth factor (TGF)-β family govern a wide range of mechanisms in brain development and in the adult, in particular neuronal/glial differentiation and survival, but also cell cycle regulation and neural stem cell maintenance. This clearly created some discrepancies in the field with some studies favouring neuronal differentiation/survival of progenitors and others favouring cell cycle exit and neural stem cell quiescence/maintenance. Here, we provide a unifying hypothesis claiming that through its regulation of neural progenitor cell (NPC) proliferation, TGF-β signalling might be responsible for (i) maintaining stem cells in a quiescent stage, and (ii) promoting survival of newly generated neurons and their functional differentiation. Therefore, we performed a detailed histological analysis of TGF-β1 signalling in the hippocampal neural stem cell niche of a transgenic mouse that was previously generated to express TGF-β1 under a tetracycline regulatable Ca-Calmodulin kinase promoter. We also analysed NPC proliferation, quiescence, neuronal survival and differentiation in relation to elevated levels of TGF-β1 in vitro and in vivo conditions. Finally, we performed a gene expression profiling to identify the targets of TGF-β1 signalling in adult NPCs. The results demonstrate that TGF-β1 promotes stem cell quiescence on one side, but also neuronal survival on the other side. Thus, considering the elevated levels of TGF-β1 in ageing and neurodegenerative diseases, TGF-β1 signalling presents a molecular target for future interventions in such conditions. PMID:24779367

  6. C/EBPβ promotes BCR-ABL-mediated myeloid expansion and leukemic stem cell exhaustion.

    PubMed

    Hayashi, Y; Hirai, H; Kamio, N; Yao, H; Yoshioka, S; Miura, Y; Ashihara, E; Fujiyama, Y; Tenen, D G; Maekawa, T

    2013-03-01

    The BCR-ABL fusion oncoprotein accelerates differentiation and proliferation of myeloid cells during the chronic phase of chronic myeloid leukemia (CP-CML). Here, the role of CCAAT/enhancer binding protein β (C/EBPβ), a regulator for 'emergency granulopoiesis,' in the pathogenesis of CP-CML was examined. C/EBPβ expression was upregulated in Lineage(-) CD34(+) CD38(-) hematopoietic stem cells (HSCs) and myeloid progenitors isolated from bone marrow of patients with CP-CML. In EML cells, a mouse HSC line, BCR-ABL upregulated C/EBPβ, at least in part, through the activation of STAT5. Myeloid differentiation and proliferation induced by BCR-ABL was significantly impaired in C/EBPβ-deficient bone marrow cells in vitro. Mice that were transplanted with BCR-ABL-transduced C/EBPβ knockout bone marrow cells survived longer than mice that received BCR-ABL-transduced wild-type (WT) bone marrow cells. Significantly higher levels of leukemic stem cells were maintained in BCR-ABL-transduced C/EBPβ-deficient cells than in BCR-ABL-transduced WT cells. These results suggest that C/EBPβ is involved in BCR-ABL-mediated myeloid expansion. Further elucidation of the molecular mechanisms underlying the C/EBPβ-mediated stem cell loss might reveal a novel therapeutic strategy for eradication of CML stem cells. PMID:22948537

  7. Tuning microenvironment modulus and biochemical composition promotes human mesenchymal stem cell tenogenic differentiation.

    PubMed

    Rehmann, Matthew S; Luna, Jesus I; Maverakis, Emanual; Kloxin, April M

    2016-05-01

    Mesenchymal stem cells (MSCs) are promising for the regeneration of tendon and ligament tissues. Toward realizing this potential, microenvironment conditions are needed for promoting robust lineage-specific differentiation into tenocytes/ligament fibroblasts. Here, we utilized a statistical design of experiments approach to examine combinations of matrix modulus, composition, and soluble factors in human MSC tenogenic/ligamentogenic differentiation. Specifically, well-defined poly(ethylene glycol)-based hydrogels were synthesized using thiol-ene chemistry providing a bioinert base for probing cell response to extracellular matrix cues. Monomer concentrations were varied to achieve a range of matrix moduli (E ∼ 10-90 kPa), and different ratios of integrin-binding peptides were incorporated (GFOGER and RGDS for collagen and fibronectin, respectively), mimicking aspects of developing tendon/ligament tissue. A face-centered central composite response surface design was utilized to understand the contributions of these cues to human MSC differentiation in the presence of soluble factors identified to promote tenogenesis/ligamentogenesis (BMP-13 and ascorbic acid). Increasing modulus and collagen mimetic peptide content increased relevant gene expression and protein production or retention (scleraxis, collagen I, tenascin-C). These findings could inform the design of materials for tendon/ligament regeneration. More broadly, the design of experiments enabled efficient data acquisition and analysis, requiring fewer replicates than if each factor had been varied one at a time. This approach can be combined with other stimuli (for example, mechanical stimulation) toward a better mechanistic understanding of differentiation down these challenging lineages. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1162-1174, 2016. PMID:26748903

  8. The potential for resident lung mesenchymal stem cells to promote functional tissue regeneration: understanding microenvironmental cues.

    PubMed

    Foronjy, Robert F; Majka, Susan M

    2012-12-01

    Tissue resident mesenchymal stem cells (MSCs) are important regulators of tissue repair or regeneration, fibrosis, inflammation, angiogenesis and tumor formation. Bone marrow derived mesenchymal stem cells (BM-MSCs) and endothelial progenitor cells (EPC) are currently being considered and tested in clinical trials as a potential therapy in patients with such inflammatory lung diseases including, but not limited to, chronic lung disease, pulmonary arterial hypertension (PAH), pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD)/emphysema and asthma. However, our current understanding of tissue resident lung MSCs remains limited. This review addresses how environmental cues impact on the phenotype and function of this endogenous stem cell pool. In addition, it examines how these local factors influence the efficacy of cell-based treatments for lung diseases. PMID:23626909

  9. Neural-Induced Human Mesenchymal Stem Cells Promote Cochlear Cell Regeneration in Deaf Guinea Pigs

    PubMed Central

    Jang, Sujeong; Cho, Hyong-Ho; Kim, Song-Hee; Lee, Kyung-Hwa; Jun, Jae Yeoul; Park, Jong-Seong; Jeong, Han-Seong

    2015-01-01

    Objectives In mammals, cochlear hair cell loss is irreversible and may result in a permanent sensorineural hearing loss. Secondary to this hair cell loss, a progressive loss of spiral ganglion neurons (SGNs) is presented. In this study, we have investigated the effects of neural-induced human mesenchymal stem cells (NI-hMSCs) from human bone marrow on sensory neuronal regeneration from neomycin treated deafened guinea pig cochleae. Methods HMSCs were isolated from the bone marrow which was obtained from the mastoid process during mastoidectomy for ear surgery. Following neural induction with basic fibroblast growth factor and forskolin, we studied the several neural marker and performed electrophysiological analysis. NI-hMSCs were transplanted into the neomycin treated deafened guinea pig cochlea. Engraftment of NI-hMSCs was evaluated immunohistologically at 8 weeks after transplantation. Results Following neural differentiation, hMSCs expressed high levels of neural markers, ionic channel markers, which are important in neural function, and tetrodotoxin-sensitive voltage-dependent sodium currents. After transplantation into the scala tympani of damaged cochlea, NI-hMSCs-injected animals exhibited a significant increase in the number of SGNs compared to Hanks balanced salt solution-injected animals. Transplanted NI-hMSCs were found within the perilymphatic space, the organ of Corti, along the cochlear nerve fibers, and in the spiral ganglion. Furthermore, the grafted NI-hMSCs migrated into the spiral ganglion where they expressed the neuron-specific marker, NeuN. Conclusion The results show the potential of NI-hMSCs to give rise to replace the lost cochlear cells in hearing loss mammals. PMID:26045904

  10. Short Report: Olfactory Ensheathing Cells Promote Differentiation of Neural Stem Cells and Robust Neurite Extension

    PubMed Central

    Sethi, Rosh; Sethi, Roshan; Redmond, Andy

    2014-01-01

    Aims The goal of this study was to gain insight into the signaling between olfactory ensheathing cells (OECs) and neural stem cells (NSCs). We sought to understand the impact of OECs on NSC differentiation and neurite extension and to begin to elucidate the factors involved in these interactions to provide new targets for therapeutic interventions. Materials and Methods We utilized lines of OECs that have been extremely well characterized in vitro and in vivo along with well studied NSCs in gels to determine the impact of the coculture in three dimensions. To further elucidate the signaling, we used conditioned media from the OECs as well as fractioned components on NSCs to determine the molecular weight range of the soluble factors that was most responsible for the NSC behavior. Results We found that the coculture of NSCs and OECs led to robust NSC differentiation and extremely long neural processes not usually seen with NSCs in three dimensional gels in vitro. Through culture of NSCs with fractioned OEC media, we determined that molecules larger than 30 kDa have the greatest impact on the NSC behavior. Conclusions Overall, our findings suggest that cocultures of NSCs and OECs may be a novel combination therapy for neural injuries including spinal cord injury (SCI). Furthermore, we have identified a class of molecules which plays a substantial role in the behavior that provides new targets for investigating pharmacological therapies. PMID:24996386

  11. CD44 promotes the migration of bone marrow-derived mesenchymal stem cells toward glioma

    PubMed Central

    YIN, QIANG; ZHOU, YANG-YANG; WANG, PENG; MA, LI; LI, PENG; WANG, XIAO-GUANG; SHE, CHUN-HUA; LI, WEN-LIANG

    2016-01-01

    Previous in vivo and in vitro studies have shown that human mesenchymal stem cells (MSCs) exhibit tropism for gliomas. However, the mechanism underlying this directed migration remains unclear. The aim of the present study was to investigate the possible mechanism underlying platelet-derived growth factor-BB (PDGF-BB)-induced chemotactic migration of bone marrow-derived MSCs (BMSCs) toward glioma. Rat glioma C6 cell-conditioned medium was utilized to evaluate the chemotactic response of BMSCs toward glioma using an in vitro migration assay. Recombinant rat PDGF-BB was added to C6 cell-conditioned medium to assess its effect on the tropism of BMSCs. The effect of PDGF-BB on the expression levels of cluster of differentiation (CD)44 in BMSCs was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence assays. The results revealed that chemotactic migration was induced in BMSCs by rat glioma C6 cell-conditioned medium, which was enhanced by PDGF-BB treatment in a dose-dependent manner. Furthermore, RT-PCR and immunofluorescence assays showed that CD44 expression was upregulated in BMSCs following treatment with 40 ng/ml PDGF-BB for 12 h. Additionally, 3-h pretreatment with the anti-CD44 neutralizing antibody OX-50 was observed to attenuate the tropism of BMSCs toward glioma in the presence or absence of PDGF-BB. The results of the present study indicate that CD44 mediates the tropism of BMSCs toward glioma, and PDGF-BB promotes the migration of BMSCs toward glioma via the upregulation of CD44 expression in BMSCs. These findings suggest CD44 inhibition may be a potential therapeutic target for the treatment of glioma. PMID:27073479

  12. Untested, unproven, and unethical: the promotion and provision of autologous stem cell therapies in Australia.

    PubMed

    McLean, Alison K; Stewart, Cameron; Kerridge, Ian

    2015-01-01

    An increasing number of private clinics in Australia are marketing and providing autologous stem cell therapies to patients. Although advocates point to the importance of medical innovation and the primacy of patient choice, these arguments are unconvincing. First, it is a stark truth that these clinics are flourishing while the efficacy and safety of autologous stem cell therapies, outside of established indications for hematopioetic stem cell transplantation, are yet to be shown. Second, few of these therapies are offered within clinical trials. Third, patients with chronic and debilitating illnesses, who are often the ones who take up these therapies, incur significant financial burdens in the expectation of benefiting from these treatments. Finally, the provision of these stem cell therapies does not follow the established pathways for legitimate medical advancement. We argue that greater regulatory oversight and professional action are necessary to protect vulnerable patients and that at this time the provision of unproven stem cell therapies outside of clinical trials is unethical. PMID:25689404

  13. G-CSF promotes neuroblastoma tumorigenicity and metastasis via STAT3-dependent cancer stem cell activation

    PubMed Central

    Agarwal, Saurabh; Lakoma, Anna; Chen, Zaowen; Hicks, John; Metelitsa, Leonid S.; Kim, Eugene S.; Shohet, Jason M.

    2015-01-01

    Increasing evidence suggests that inflammatory cytokines play a critical role in tumor initiation and progression. We previously isolated a Cancer Stem Cell-like (CSC) subpopulation in neuroblastoma based on differential expression of the receptor for G-CSF (Granulocyte-Colony Stimulating Factor). Here we demonstrate that G-CSF selectively activates signal transducer and activator of transcription 3 (STAT3) within neuroblastoma CSC subpopulations, promoting their expansion in vitro and in vivo. Exogenous G-CSF enhances tumor growth and metastasis in human xenograft and murine neuroblastoma tumor models. In response to G-CSF, STAT3 transcriptionally activates the G-CSF receptor (encoded by CSF3R), creating a CSC sustaining positive-feedback loop. Blockade of G-CSF/STAT3 signaling loop with either anti-G-CSF antibody or STAT3 inhibitor depletes the CSC subpopulation within tumors, driving correlated tumor regression, blocking metastasis and increasing chemosensitivity. Taken together, these data define G-CSF as a tumorigenic growth factor for neuroblastoma and suggest a comprehensive re-evaluation of the clinical use of G-CSF in these patients. Our data also demonstrate that direct targeting of the G-CSF/STAT3 signaling represents a novel therapeutic approach for neuroblastoma. PMID:25908586

  14. Activation of Wnt3a signaling promotes myogenic differentiation of mesenchymal stem cells in mdx mice

    PubMed Central

    Shang, Yan-chang; Wang, Shu-hui; Xiong, Fu; Peng, Fu-ning; Liu, Zhen-shan; Geng, Jia; Zhang, Cheng

    2016-01-01

    Aim: Duchenne muscular dystrophy (DMD) is an X-linked genetic muscular disorder with no effective treatment at present. Mesenchymal stem cell (MSC) transplantation has been used to treat DMD, but the efficiency is low. Our previous studies show that activation of Wnt3a signaling promotes myogenic differentiation of MSCs in vitro. Here we report an effective MSC transplantation therapy in mdx mice by activation of Wnt3a signaling. Methods: MSCs were isolated from mouse bone marrow, and pretreated with Wnt3a-conditioned medium (Wnt3a-CM), then transplanted into mdx mice. The recipient mice were euthanized at 4, 8, 12, 16 weeks after the transplantation, and muscle pathological changes were examined. The expression of dystrophin in muscle was detected using immunofluorescence staining, RT-PCR and Western blotting. Results: Sixteen weeks later, transplantation of Wnt3a-pretreated MSCs in mdx mice improved the characteristics of dystrophic muscles evidenced by significant reductions in centrally nucleated myofibers, the variability range of cross-sectional area (CSA) and the connective tissue area of myofibers. Furthermore, transplantation of Wnt3a-pretreated MSCs in mdx mice gradually and markedly increased the expression of dystrophin in muscle, and improved the efficiency of myogenic differentiation. Conclusion: Transplantation of Wnt3a-pretreated MSCs in mdx mice results in long-term amelioration of the dystrophic phenotype and restores dystrophin expression in muscle. The results suggest that Wnt3a may be a promising candidate for the treatment of DMD. PMID:27133298

  15. [Macrophages promote the migration of neural stem cells into mouse spinal cord injury site].

    PubMed

    Cheng, Zhijian; Zhu, Wen; Li, Haopeng; He, Xijing

    2016-09-01

    Objective To explore the role of macrophages in the migration of neural stem cells (NSCs) in vivo and in vitro . Methods NSCs with green fluorescent protein (GFP) were isolated from GFP transgenic mice and the immunofluorescence cytochemical staining of nestin was used to identify NSCs. After spinal cord injury was induced, the tissue level of macrophage chemotactic protein-1 (MCP-1) mRNA was detected using quantitative real time PCR. The migration of GFP-NSCs was investigated 1 week after GFP-NSCs were injected into both sides of the damaged area. The effect of macrophage on the migration of NSCs in vitro was tested by Transwell(TM) system and the content of MCP-1 was detected by ELISA. Results NSCs highly expressed nestin. Compared with the control group, the level of MCP-1 mRNA significantly increased in the spinal cord injury group. The NSCs which were injected into the spinal cord migrated into the center of the injured site where F4/80 was highly expressed. Macrophages significantly increased the number of migrating NSCs in vitro and the secretion of MCP-1. Conclusion Macrophages induce NSC migrating into the spinal cord injury site possibly through promoting the secretion of MCP-1. PMID:27609570

  16. CD14{sup +} monocytes promote the immunosuppressive effect of human umbilical cord matrix stem cells

    SciTech Connect

    Wang, Ding; TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin ; Chen, Ke; TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin ; Du, Wei Ting; Han, Zhi-Bo; TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin ; Ren, He; Chi, Ying; TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin ; and others

    2010-09-10

    Here, the effect of CD14{sup +} monocytes on human umbilical cord matrix stem cell (hUC-MSC)-mediated immunosuppression was studied in vitro. hUC-MSCs exerted a potent inhibitory effect on the proliferation and interferon-{gamma} (IFN-{gamma}) secretion capacities of CD4{sup +} and CD8{sup +} T cells in response to anti-CD3/CD28 stimulation. Transwell co-culture system revealed that the suppressive effect was primarily mediated by soluble factors. Addition of prostaglandin synthesis inhibitors (indomethacin or NS-398) almost completely abrogated the immunosuppression activity of hUC-MSCs, identifying prostaglandin E{sub 2} (PGE{sub 2}) as an important soluble mediator. CD14{sup +} monocytes were found to be able to enhance significantly the immunosuppressive effect of hUC-MSCs in a dose-dependent fashion. Moreover, the inflammatory cytokine IL-1{beta}, either exogenously added or produced by CD14{sup +} monocytes in culture, could trigger expression of high levels of PGE{sub 2} by hUC-MSCs, whereas inclusion of the IL-1 receptor antagonist (IL-1RA) in the culture down-regulated not only PGE{sub 2} expression, but also reversed the promotional effect of CD14{sup +} monocytes and partially restored CD4{sup +} and CD8{sup +} T cell proliferation and IFN-{gamma} secretion. Our data demonstrate an important role of monocytes in the hUC-MSC-induced immunomodulation, which may have important implications in future efforts to explore the clinical potentials of hUC-MSCs.

  17. Activation of mesenchymal stem cells by macrophages promotes tumor progression through immune suppressive effects

    PubMed Central

    Jia, Xiao-hua; Feng, Guo-wei; Wang, Zhong-liang; Du, Yang; Shen, Chen; Hui, Hui; Peng, Dong; Li, Zong-jin; Kong, De-ling; Tian, Jie

    2016-01-01

    Cancer development and progression is linked to tumor-associated macrophages (TAMs). Distinct TAMs subsets perform either protective or pathogenic effects in cancer. A protective role in carcinogenesis has been described for M1 macrophages, which activate antitumor mechanisms. By comparison, TAMs isolated from solid and metastatic tumors have a suppressive M2-like phenotype, which could support multiple aspects of tumor progression. Currently, it has not been clearly understood how macrophages in tumor-associated stroma could be hijacked to support tumor growth. Mesenchymal stem cells (MSCs) actively interact with components of the innate immune system and display both anti-inflammatory and pro-inflammatory effects. Here, we tested whether MSCs could favor the tumor to escape from immunologic surveillance in the presence of M1 macrophages. We found that MSCs educated by M1 condition medium (cMSCs) possessed a greatly enhanced ability in promoting tumor growth in vivo. Examination of cytokines/chemokines showed that the cMSCs acquired a regulatory profile, which expressed high levels of iNOS and MCP1. Consistent with an elevated MCP1 expression in cMSCs, the tumor-promoting effect of the cMSCs depended on MCP1 mediated macrophage recruitment to tumor sites. Furthermore, IL-6 secreted by the cMSCs could polarize infiltrated TAMs into M2-like macrophages. Therefore, when macrophages changed into M1 pro-inflammation type in tumor microenvironment, the MSCs would act as poor sensors and switchers to accelerate tumor growth. PMID:26988913

  18. Mussel-inspired alginate gel promoting the osteogenic differentiation of mesenchymal stem cells and anti-infection.

    PubMed

    Zhang, Shiwen; Xu, Kaige; Darabi, Mohammad Ali; Yuan, Quan; Xing, Malcolm

    2016-12-01

    Alginate hydrogels have been used in cell encapsulation for many years but a prevalent issue with pure alginates is that they are unable to provide enough bioactive properties to interact with mammalian cells. This paper discusses the modification of alginate with mussel-inspired dopamine for cell loading and anti-infection. Mouse bone marrow stem cells were immobilized into alginate and alginate-dopamine beads and fibers. Through live-dead and MTT assay, alginates modified by dopamine promoted cell viability and proliferation. In vitro cell differentiation results showed that such an alginate-dopamine gel can promote the osteogenic differentiation of mesenchymal stem cell after PCR and ALP assays. In addition to that, the adhesive prosperities of dopamine allowed for coating the surface of alginate-dopamine gel with silver nanoparticles, which provided the gel with significant antibacterial characteristics. Overall, these results demonstrate that a dopamine-modified alginate gel can be a great tool for cell encapsulation to promote cell proliferation and can be applied to bone regeneration, especially in contaminated bone defects. PMID:27612740

  19. Mesenchymal stem cells from adipose and bone marrow promote angiogenesis via distinct cytokine and protease expression mechanisms

    PubMed Central

    Kachgal, Suraj; Putnam, Andrew J.

    2012-01-01

    Using a fibrin-based angiogenesis model, we have established that there is no canonical mechanism used by ECs to degrade the surrounding extracellular matrix (ECM), but rather the set of proteases used is dependent on the mural cells providing the angiogenic cues. Mesenchymal stem cells (MSCs) originating from different tissues, which are thought to be phenotypically similar, promote angiogenesis through distinct mechanisms. Specifically, adipose-derived stem cells (ASCs) promote utilization of the plasminogen activator-plasmin axis by ECs as the primary means of vessel invasion and elongation in fibrin. Matrix metalloproteinases (MMPs) serve a purpose in regulating capillary diameter and possibly in stabilizing the nascent vessels. These proteolytic mechanisms are more akin to those involved in fibroblast-mediated angiogenesis than to those in bone marrow-derived stem cell (BMSC)-mediated angiogenesis. In addition, expression patterns of angiogenic factors such as urokinase plasminogen activator (uPA), hepatocyte growth factor (HGF), and tumor necrosis factor alpha (TNFα) were similar for ASC and fibroblast-mediated angiogenesis, and in direct contrast to BMSC-mediated angiogenesis. The present study illustrates that the nature of the heterotypic interactions between mural cells and endothelial cells depend on the identity of the mural cell used. Even MSCs which are shown to behave phenotypically similar do not stimulate angiogenesis via the same mechanisms. PMID:21104120

  20. Paracrine activation of WNT/β-catenin pathway in uterine leiomyoma stem cells promotes tumor growth

    PubMed Central

    Ono, Masanori; Yin, Ping; Navarro, Antonia; Moravek, Molly B.; Coon, John S.; Druschitz, Stacy A.; Serna, Vanida Ann; Qiang, Wenan; Brooks, David C.; Malpani, Saurabh S.; Ma, Jiajia; Ercan, Cihangir Mutlu; Mittal, Navdha; Monsivais, Diana; Dyson, Matthew T.; Yemelyanov, Alex; Maruyama, Tetsuo; Chakravarti, Debabrata; Kim, J. Julie; Kurita, Takeshi; Gottardi, Cara J.; Bulun, Serdar E.

    2013-01-01

    Uterine leiomyomas are extremely common estrogen and progesterone-dependent tumors of the myometrium and cause irregular uterine bleeding, severe anemia, and recurrent pregnancy loss in 15–30% of reproductive-age women. Each leiomyoma is thought to arise from a single mutated myometrial smooth muscle stem cell. Leiomyoma side-population (LMSP) cells comprising 1% of all tumor cells and displaying tumor-initiating stem cell characteristics are essential for estrogen- and progesterone-dependent in vivo growth of tumors, although they have remarkably lower estrogen/progesterone receptor levels than mature myometrial or leiomyoma cells. However, how estrogen/progesterone regulates the growth of LMSP cells via mature neighboring cells is unknown. Here, we demonstrate a critical paracrine role of the wingless-type (WNT)/β-catenin pathway in estrogen/progesterone-dependent tumorigenesis, involving LMSP and differentiated myometrial or leiomyoma cells. Estrogen/progesterone treatment of mature myometrial cells induced expression of WNT11 and WNT16, which remained constitutively elevated in leiomyoma tissues. In LMSP cells cocultured with mature myometrial cells, estrogen-progesterone selectively induced nuclear translocation of β-catenin and induced transcriptional activity of its heterodimeric partner T-cell factor and their target gene AXIN2, leading to the proliferation of LMSP cells. This effect could be blocked by a WNT antagonist. Ectopic expression of inhibitor of β-catenin and T-cell factor 4 in LMSP cells, but not in mature leiomyoma cells, blocked the estrogen/progesterone-dependent growth of human tumors in vivo. We uncovered a paracrine role of the WNT/β-catenin pathway that enables mature myometrial or leiomyoma cells to send mitogenic signals to neighboring tissue stem cells in response to estrogen and progesterone, leading to the growth of uterine leiomyomas. PMID:24082114

  1. RSPO2 enriches LGR5+ spheroid colon cancer stem cells and promotes its metastasis by epithelial-mesenchymal transition

    PubMed Central

    Zhang, Shi; Han, Xiaoyan; Wei, Bo; Fang, Jiafeng; Wei, Hongbo

    2016-01-01

    Colon cancer stem cells (CCSCs) account for the tumorigenicity of colon cancer and promote its progression and metastasis. RSPO2, the agonist of canonical Wnt/beta-catenin pathway and serves as the growth factor of intestinal stem cells (ISCs), is considered playing an important role in CCSCs. However, the specific function of RSPO2 in CCSCs remains unclear. In this study, we demonstrated that RSPO2 was highly expressed in CCSCs-enriched HCT116 spheroid cells. Elevates the concentration of RSPO2 in medium in favor of enriching the LGR5+ cells and increasing the LGR5 expression in HCT116 spheroid cells, meanwhile silencing of RSPO2 by small interfering RNA inhibits LGR5 expression in HCT116 spheroid cells. In addition, RSPO2 promotes spheres formation but has little effect on the proliferation of HCT116 spheroid cells in vitro. Moreover, RSPO2 also promotes the invasion of HCT116 spheroid cells through enhancing Epithelial-mesenchymal transition (EMT). These findings suggests that RSPO2 is a potential growth factor for CCSCs, helps enriching the CCSCs by serum-free DMEM/F12 medium (SFM) culture and plays a vital role in the metastasis of colon cancer. PMID:27158331

  2. CpG island erosion, polycomb occupancy and sequence motif enrichment at bivalent promoters in mammalian embryonic stem cells

    PubMed Central

    Mantsoki, Anna; Devailly, Guillaume; Joshi, Anagha

    2015-01-01

    In embryonic stem (ES) cells, developmental regulators have a characteristic bivalent chromatin signature marked by simultaneous presence of both activation (H3K4me3) and repression (H3K27me3) signals and are thought to be in a ‘poised’ state for subsequent activation or silencing during differentiation. We collected eleven pairs (H3K4me3 and H3K27me3) of ChIP sequencing datasets in human ES cells and eight pairs in murine ES cells, and predicted high-confidence (HC) bivalent promoters. Over 85% of H3K27me3 marked promoters were bivalent in human and mouse ES cells. We found that (i) HC bivalent promoters were enriched for developmental factors and were highly likely to be differentially expressed upon transcription factor perturbation; (ii) murine HC bivalent promoters were occupied by both polycomb repressive component classes (PRC1 and PRC2) and grouped into four distinct clusters with different biological functions; (iii) HC bivalent and active promoters were CpG rich while H3K27me3-only promoters lacked CpG islands. Binding enrichment of distinct sets of regulators distinguished bivalent from active promoters. Moreover, a ‘TCCCC’ sequence motif was specifically enriched in bivalent promoters. Finally, this analysis will serve as a resource for future studies to further understand transcriptional regulation during embryonic development. PMID:26582124

  3. Allogeneic adipose-derived stem cells promote survival of fat grafts in immunocompetent diabetic rats.

    PubMed

    Zhang, Jun; Bai, Xiaozhi; Zhao, Bin; Wang, Yunchuan; Su, Linlin; Chang, Peng; Wang, Xujie; Han, Shichao; Gao, Jianxin; Hu, Xiaolong; Hu, Dahai; Liu, Xiaoyan

    2016-05-01

    Autologous adipose-derived stem cells (ADSCs) can protect fat grafts in cell-assisted lipotransfer (CAL). However, diabetes alters the intrinsic properties of ADSCs and impairs their function so that they lack these protective effects. We investigate whether allogeneic ADSCs from healthy donors could protect fat grafts in immunocompetent diabetic rats. Syngeniec adipose tissues and ADSCs were derived from diabetic Lewis (LEW) rats, whereas allogeneic ADSCs were from healthy brown-Norway rats. A grafted mixture containing 0.7 ml granule fat and 0.3 ml 6 × 10(6) allogeneic/syngeneic ADSCs was injected subcutaneously on the skulls of diabetic LEW rats. Fat samples were harvested to evaluate the levels of injury and vascularization as shown by perilipin A, CD34 and VEGF at 14 days. The immune response was evaluated with a lymphocytotoxicity test and the CD4/CD8 ratio in peripheral blood at 14 days. The volume retention of fat grafts was measured at 3 months. Healthy allogeneic ADSCs increased the expression levels of perilipin A, CD34 and VEGF at 14 days. The volume retention of fat grafts was improved by allogeneic ADSCs at 3 months. ADSCs were demonstrated to have low immunogenicity by the lymphocyte proliferation test and immunophenotype including MHC and co-stimulatory markers. The lymphocytotoxicity test and CD4/CD8 ratio indicated no obvious immune response elicited by allogeneic ADSCs. Thus, healthy allogeneic ADSCs can promote the survival of fat grafts in this immunocompetent diabetic rat model, with little or no obvious immune rejection. PMID:26662284

  4. miR-367 promotes proliferation and stem-like traits in medulloblastoma cells

    PubMed Central

    Kaid, Carolini; Silva, Patrícia B G; Cortez, Beatriz A; Rodini, Carolina O; Semedo-Kuriki, Patricia; Okamoto, Oswaldo K

    2015-01-01

    In medulloblastoma, abnormal expression of pluripotency factors such as LIN28 and OCT4 has been correlated with poor patient survival. The miR-302/367 cluster has also been shown to control self-renewal and pluripotency in human embryonic stem cells and induced pluripotent stem cells, but there is limited, mostly correlational, information about these pluripotency-related miRNA in cancer. We evaluated whether aberrant expression of such miRNA could affect tumor cell behavior and stem-like traits, thereby contributing to the aggressiveness of medulloblastoma cells. Basal expression of primary and mature forms of miR-367 were detected in four human medulloblastoma cell lines and expression of the latter was found to be upregulated upon enforced expression of OCT4A. Transient overexpression of miR-367 significantly enhanced tumor features typically correlated with poor prognosis; namely, cell proliferation, 3-D tumor spheroid cell invasion and the ability to generate neurosphere-like structures enriched in CD133 expressing cells. A concurrent downregulation of the miR-367 cancer-related targets RYR3, ITGAV and RAB23, was also detected in miR-367-overexpressing cells. Overall, these findings support the pro-oncogenic activity of miR-367 in medulloblastoma and reveal a possible mechanism contributing to tumor aggressiveness, which could be further explored to improve patient stratification and treatment of this important type of pediatric brain cancer. PMID:26250335

  5. Production of interleukin‑4 in CD133+ cervical cancer stem cells promotes resistance to apoptosis and initiates tumor growth.

    PubMed

    Liu, Chun-Tao; Xin, Ying; Tong, Chun-Yan; Li, Bing; Bao, Hong-Li; Zhang, Cai-Yun; Wang, Xue-Hui

    2016-06-01

    The cancer stem cell (CSC) theory suggests that cancer growth and invasion is dictated by the small population of CSCs within the heterogenous tumor. The aim of the present study was to elucidate the cause for chemotherapy failure and the resistance of CSCs to apoptosis. A total of ~2.3% cluster of differentiation (CD)133+ cancer stem‑like side population (SP) cells were identified in cases of uterine cervical cancer. These CD133+ SP cells were found to potently initiate tumor growth and invasion, as they exhibit transcriptional upregulation of stemness genes, including octamer‑binding transcription factor‑4, B‑cell‑specific Moloney murine leukemia virus insertion site‑1, epithelial cell adhesion molecule, (sex determining region Y)‑box 2, Nestin and anti‑apoptotic B cell lymphoma‑2. In addition, the CD133+ SP cells showed resistance to multi‑drug treatment and apoptosis. The present study further showed that the secretion of interleukin‑4 (IL‑4) in CD133+ cervical cancer SP cells promoted cell proliferation and prevented the SP cells from apoptosis. Following the neutralization of IL‑4 with anti‑IL‑4 antibody, the CD133+ SP cells were more sensitive to drug treatment and apoptosis. Therefore, the data obtained in the present study suggested that the autocrine secretion of IL‑4 promotes increased survival and resistance to cell death in CSCs. PMID:27121303

  6. Stem cell glycolipids.

    PubMed

    Yanagisawa, Makoto

    2011-09-01

    Glycolipids are compounds containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety. Because of their expression patterns and the intracellular localization patterns, glycolipids, including stage-specific embryonic antigens (SSEA-3, SSEA-4, and possibly SSEA-1) and gangliosides (e.g., GD3, GD2, and A2B5 antigens), have been used as marker molecules of stem cells. In this review, I will introduce glycolipids expressed in pluripotent stem cells (embryonic stem cells, induced pluripotent stem cells, very small embryonic-like stem cells, amniotic stem cells, and multilineage-differentiating stress enduring cells), multipotent stem cells (neural stem cells, mesenchymal stem cells, fetal liver multipotent progenitor cells, and hematopoietic stem cells), and cancer stem cells (brain cancer stem cells and breast cancer stem cells), and discuss their availability as biomarkers for identifying and isolating stem cells. PMID:21161592

  7. A functional polyester carrying free hydroxyl groups promotes the mineralization of osteoblast and human mesenchymal stem cell extracellular matrix.

    PubMed

    Bi, Xiaoping; You, Zhengwei; Gao, Jin; Fan, Xianqun; Wang, Yadong

    2014-06-01

    Functional groups can control biointerfaces and provide a simple way to make therapeutic materials. We recently reported the design and synthesis of poly(sebacoyl diglyceride) (PSeD) carrying a free hydroxyl group in its repeating unit. This paper examines the use of this polymer to promote biomineralization for application in bone tissue engineering. PSeD promoted more mineralization of extracellular matrix secreted by human mesenchymal stem cells and rat osteoblasts than poly(lactic-co-glycolic acid) (PLGA), which is currently widely used in bone tissue engineering. PSeD showed in vitro osteocompatibility and in vivo biocompatibility that matched or surpassed that of PLGA, as well as supported the attachment, proliferation and differentiation of rat osteoblasts and human mesenchymal stem cells. This demonstrates the potential of PSeD for use in bone regeneration. PMID:24560799

  8. FGFR1 promotes the stem cell-like phenotype of FGFR1-amplified non-small cell lung cancer cells through the Hedgehog pathway

    PubMed Central

    Ji, Wenxiang; Yu, Yongfeng; Li, Ziming; Wang, Guan; Li, Fan; Xia, Weiliang; Lu, Shun

    2016-01-01

    Cancer stem cell-like phenotype is critical for tumor formation and treatment resistance. FGFR1 is found to be amplified in non-small cell lung cancer, particularly in the lung squamous cell cancer (LSCC). Whether FGFR1 contributes to the maintenance of stem cell-like phenotype of FGFR1-amplified lung cancer cells remains elusive. In this study, treatment with FGFR1 inhibitor AZD4547 suppressed the growth of tumor spheres and reduced ALDH positive proportion in FGFR1-amplified lung cancer cells in vitro, as well as inhibited the growth of oncospheres and parental cells in xenograft models. Knockdown of FGFR1 recaptured the similar effect as AZD4547 in vitro. Furthermore, activation of FGFR1 and subsequently its downstream ERK signaling enhanced the expression and transcriptional activity of GLI2, which could be blocked by FGFR1 inhibitor/silencing or ERK inhibitor. Knockdown of GLI2 directly inhibited the stem-like phenotype of FGFR1-amilified cells, whereas overexpression of GLI2 sufficiently rescued the phenotype caused by FGFR1 knockdown. Notably we also identified a correlation between FGFR1 and GLI2 expressions from clinical data, as well as an inverse relationship with progression free survival (PFS). Together our study suggests that the FGFR1/GLI2 axis promotes the lung cancer stem cell-like phenotype. These results support a rational strategy of combination of FGFR1 and GLI inhibitors for treatment of FGFR1-amplified lung cancers, especially LSCC. PMID:26936993

  9. EGFR Kinase Promotes Acquisition of Stem Cell-Like Properties: A Potential Therapeutic Target in Head and Neck Squamous Cell Carcinoma Stem Cells

    PubMed Central

    Rahimy, Elham; Kuo, Selena Z.; Wang-Rodriguez, Jessica; Lopez, Jay Patrick; Blair, Katherine J.; Yu, Michael Andrew; Haas, Martin; Brumund, Kevin T.; Altuna, Xabier; Patel, Andrew; Weisman, Robert A.; Ongkeko, Weg M.

    2012-01-01

    Members of the EGFR/ErbB family of tyrosine kinases are found to be highly expressed and deregulated in many cancers, including head and neck squamous cell carcinoma (HNSCC). The ErbB family, including EGFR, has been demonstrated to play key roles in metastasis, tumorigenesis, cell proliferation, and drug resistance. Recently, these characteristics have been linked to a small subpopulation of cells classified as cancer stem cells (CSCs) which are believed to be responsible for tumor initiation and maintenance. In this study, we investigated the possible role of EGFR as a regulator of “stemness” in HNSCC cells. Activation of EGFR by the addition of EGF ligand or ectopic expression of EGFR in two established HNSCC cell lines (UMSCC-22B and HN-1) resulted in the induction of CD44, BMI-1, Oct-4, NANOG, CXCR4, and SDF-1. Activation of EGFR also resulted in increased tumorsphere formation, a characteristic ability of cancer stem cells. Conversely, treatment with the EGFR kinase inhibitor, Gefinitib (Iressa), resulted in decreased expression of the aforementioned genes, and loss of tumorsphere-forming ability. Similar trends were observed in a 99.9% CD44 positive stem cell culture derived from a fresh HNSCC tumor, confirming our findings for the cell lines. Additionally, we found that these putative cancer stem cells, when treated with Gefitinib, possessed a lower capacity to invade and became more sensitive to cisplatin-induced death in vitro. These results suggest that EGFR plays critical roles in the survival, maintenance, and function of cancer stem cells. Drugs that target EGFR, perhaps administered in combination with conventional chemotherapy, might be an effective treatment for HNSCC. PMID:22384257

  10. University Festival Promotes STEM Education

    ERIC Educational Resources Information Center

    Quagliata, Andrew B.

    2015-01-01

    STEM education is argued as an essential ingredient in preparing our children for careers of the future. This study describes a university festival that includes the promotion of STEM-related career interests in young people among its goals. A total of 203 participants between the age of 7 and 17 completed both pre-event and post-event surveys. In…

  11. Raspberry ketone promotes the differentiation of C3H10T1/2 stem cells into osteoblasts.

    PubMed

    Takata, Tomoyo; Morimoto, Chie

    2014-03-01

    The decrease in the bone mass associated with osteoporosis caused by ovariectomy, aging, and other conditions is accompanied by an increase in bone marrow adipose tissue. The balance between osteoblasts and adipocytes is influenced by a reciprocal relationship. The development of modalities to promote local/systemic bone formation by inhibiting bone marrow adipose tissue is important in the treatment of fractures or metabolic bone diseases such as osteoporosis. In this study, we examined whether raspberry ketone [4-(4-hydroxyphenyl)butan-2-one; RK], which is one of the major aromatic compounds of red raspberry and exhibits anti-obesity action, could promote osteoblast differentiation in C3H10T1/2 stem cells. Confluent C3H10T1/2 stem cells were treated for 6 days with 10-100 μg/mL of RK in culture medium containing 10 nM all-trans-retinoic acid (ATRA) or 300 ng/mL recombinant human bone morphogenetic protein (rhBMP)-2 protein as an osteoblast-differentiating agent. RK in the presence of ATRA increased alkaline phosphatase (ALP) activity in a dose-dependent manner. RK in the presence of rhBMP-2 also increased ALP activity. RK in the presence of ATRA also increased the levels of mRNAs of osteocalcin, α1(I) collagen, and TGF-βs (TGF-β1, TGF-β2, and TGF-β3) compared with ATRA only. RK promoted the differentiation of C3H10T1/2 stem cells into osteoblasts. However, RK did not affect the inhibition of early-stage adipocyte differentiation. Our results suggest that RK enhances the differentiation of C3H10T1/2 stem cells into osteoblasts, and it may promote bone formation by an action unrelated to adipocyte differentiation. PMID:24404978

  12. UV-activated 7-dehydrocholesterol-coated titanium implants promote differentiation of human umbilical cord mesenchymal stem cells into osteoblasts.

    PubMed

    Satué, María; Ramis, Joana M; Monjo, Marta

    2016-01-01

    Vitamin D metabolites are essential for bone regeneration and mineral homeostasis. The vitamin D precursor 7-dehydrocholesterol can be used after UV irradiation to locally produce active vitamin D by osteoblastic cells. Furthermore, UV-irradiated 7-dehydrocholesterol is a biocompatible coating for titanium implants with positive effects on osteoblast differentiation. In this study, we examined the impact of titanium implants surfaces coated with UV-irradiated 7-dehydrocholesterol on the osteogenic differentiation of human umbilical cord mesenchymal stem cells. First, the synthesis of cholecalciferol (D3) was achieved through the incubation of the UV-activated 7-dehydrocholesterol coating for 48 h at 23℃. Further, we investigated in vitro the biocompatibility of this coating in human umbilical cord mesenchymal stem cells and its potential to enhance their differentiation towards the osteogenic lineage. Human umbilical cord mesenchymal stem cells cultured onto UV-irradiated 7-dehydrocholesterol-coated titanium implants surfaces, combined with osteogenic supplements, upregulated the gene expression of several osteogenic markers and showed higher alkaline phosphatase activity and calcein blue staining, suggesting increased mineralization. Thus, our results show that the use of UV irradiation on 7-dehydrocholesterol -treated titanium implants surfaces generates a bioactive coating that promotes the osteogenic differentiation of human umbilical cord mesenchymal stem cells, with regenerative potential for improving osseointegration in titanium-based bone anchored implants. PMID:25899927

  13. SREBP-2 promotes stem cell-like properties and metastasis by transcriptional activation of c-Myc in prostate cancer

    PubMed Central

    Li, Xiangyan; Wu, Jason Boyang; Li, Qinlong; Shigemura, Katsumi; Chung, Leland W.K.; Huang, Wen-Chin

    2016-01-01

    Sterol regulatory element-binding protein-2 (SREBP-2) transcription factor mainly controls cholesterol biosynthesis and homeostasis in normal cells. The role of SREBP-2 in lethal prostate cancer (PCa) progression remains to be elucidated. Here, we showed that expression of SREBP-2 was elevated in advanced pathologic grade and metastatic PCa and significantly associated with poor clinical outcomes. Biofunctional analyses demonstrated that SREBP-2 induced PCa cell proliferation, invasion and migration. Furthermore, overexpression of SREBP-2 increased the PCa stem cell population, prostasphere-forming ability and tumor-initiating capability, whereas genetic silencing of SREBP-2 inhibited PCa cell growth, stemness, and xenograft tumor growth and metastasis. Clinical and mechanistic data showed that SREBP-2 was positively correlated with c-Myc and induced c-Myc activation by directly interacting with an SREBP-2-binding element in the 5′-flanking c-Myc promoter region to drive stemness and metastasis. Collectively, these clinical and experimental results reveal a novel role of SREBP-2 in the induction of a stem cell-like phenotype and PCa metastasis, which sheds light on translational potential by targeting SREBP-2 as a promising therapeutic approach in PCa. PMID:26883200

  14. High Runx1 levels promote a reversible more differentiated cell-state in hair follicle stem cells during quiescence

    PubMed Central

    Lee, Song Eun; Sada, Aiko; Zhang, Meng; McDermitt, David J.; Lu, Shu Yang; Kemphues, Kenneth J.; Tumbar, Tudorita

    2014-01-01

    Quiescent hair follicle (HF) bulge stem cells (SCs) differentiate to early progenitor (EP) hair germ (HG) cells, which divide to produce transit-amplifying (TA) matrix cells. EPs can revert to SCs upon injury, but whether this de-differentiation occurs in normal HF homeostasis (hair cycle), and the mechanisms regulating both differentiation and de-differentiation are unclear. Here we use lineage tracing, gain of function, transcriptional profiling, and functional assays to examine the role of observed endogenous Runx1 level changes in the hair cycle. We find that forced Runx1 expression induces hair degeneration (catagen) and simultaneously promotes changes in the quiescent bulge SC transcriptome towards a cell-state resembling the EP HG fate. This cell-state transition is functionally reversible. We propose that SC differentiation and de-differentiation are likely to occur during normal HF degeneration and niche restructuring in response to changes in endogenous Runx1 levels associated with SC location with respect to the niche. PMID:24462289

  15. Mesenchymal stem cells promote colorectal cancer progression through AMPK/mTOR-mediated NF-κB activation

    PubMed Central

    Wu, Xiao-Bing; Liu, Yang; Wang, Gui-Hua; Xu, Xiao; Cai, Yang; Wang, Hong-Yi; Li, Yan-Qi; Meng, Hong-Fang; Dai, Fu; Jin, Ji-De

    2016-01-01

    Mesenchymal stem cells (MSCs) exert a tumor-promoting effect in a variety of human cancers. This study was designed to identify the molecular mechanisms related to the tumor-promoting effect of MSCs in colorectal cancer. In vitro analysis of colorectal cancer cell lines cultured in MSC conditioned media (MSC-CM) showed that MSC-CM significantly promoted the progression of the cancer cells by enhancing cell proliferation, migration and colony formation. The tumorigenic effect of MSC-CM was attributed to altered expression of cell cycle regulatory proteins and inhibition of apoptosis. Furthermore, MSC-CM induced high level expression of a number of pluripotency factors in the cancer cells. ELISAs revealed MSC-CM contained higher levels of IL-6 and IL-8, which are associated with the progression of cancer. Moreover, MSC-CM downregulated AMPK mRNA and protein phosphorylation, but upregulated mTOR mRNA and protein phosphorylation. The NF-κB pathway was activated after addition of MSC-CM. An in vivo model in Balb/C mice confirmed the ability of MSC-CM to promote the invasion and proliferation of colorectal cancer cells. This study indicates that MSCs promote the progression of colorectal cancer via AMPK/mTOR-mediated NF-κB activation. PMID:26892992

  16. Boron Nitride Nanotubes Reinforce Tricalcium Phosphate Scaffolds and Promote the Osteogenic Differentiation of Mesenchymal Stem Cells.

    PubMed

    Shuai, Cijun; Gao, Chengde; Feng, Pei; Xiao, Tao; Yu, Kun; Deng, Youwen; Peng, Shuping

    2016-05-01

    Incorporating boron nitride nanotubes (BNNTs) into ceramic matrices is a promising strategy for obtaining multifunctional composites. In this study, the application of BNNTs in reinforcing β-tricalcium phosphate (β-TCP) scaffolds manufactured using laser sintering is demonstrated. BNNTs contribute to the effective inhibition of both grain growth and phase transformation in β-TCP. Moreover, they can strengthen the grain boundaries and boost the fracture mode transition from intergranular to transgranular. BNNTs play an active role in reinforcing β-TCP in terms of load transfer and energy absorption by the synergistic mechanisms of pull-out, peel-off, crack bridging and deflection. With a BNNT content of 4 wt%, the elastic modulus, hardness, compressive strength and fracture toughness of β-TCP increase by 46%, 39%, 109% and 35%, respectively. Umbilical cord mesenchymal stem cells (UC-MSCs) were isolated with high purity, and surface molecule characterization revealed that they were CD90+, CD29+, CD73+, CD31-, CD34- and CD45-. UC-MSCs on BNNTs/β-TCP scaffolds were characterized by more positive Alizarin Red staining as well as up-regulated expression of osteoblast markers, as revealed by quantitative real-time reverse transcriptase polymerase chain reaction analysis and immunofluorescence staining. These results are the first to demonstrate that BNNTs promote the osteogenic differentiation of UC-MSCs, indicating good osteoinductive properties for use in bone scaffolds. This study paves the way for the potential use of a BNNT/β-TCP scaffold in bone repair. PMID:27305816

  17. Could MDMA Promote Stemness Characteristics in Mouse Embryonic Stem Cells via mGlu5 Metabotropic Glutamate Receptors?

    PubMed Central

    Meamar, Rokhsareh; Karamali, Fereshte; Mousavi, Seyed Ali; Baharvand, Hossein; Nasr-Esfahani, Mohammad Hossein

    2012-01-01

    Objective: Ecstasy, or 3, 4 (±) methylenedioxymethamphetamine (MDMA), is a potent neurotoxic drug. One of the mechanisms for its toxicity is the secondary release of glutamate. Mouse embryonic stem cells (mESCs) express only one glutamate receptor, the metabotropic glutamate receptor 5 (mGlu5), which is involved in the maintenance and self-renewal of mESCs. This study aims to investigate whether MDMA could influence self-renewal via the mGlu5 receptor in mESCs. Materials and Methods: In this expremental study, we used immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR) to determine the presence of the mGlu5 receptor in mESCs. The expression of mGlu5 was evaluated after MDMA was added to mESCs throughout neural precursor cell formation as group 1 and during neural precursor cell differentiation as group 2. The stemness characteristic in treated mESCs by immunofluorescence and flow cytometry was studied. Finally, caspase activity was evaluated by fluorescence staining in the treated group. One-way ANOVA or repeated measure of ANOVA according to the experimental design was used for statistical analyses. Results: In this study mGlu5 expression was shown in mESCs. In terms of neuronal differentiation, MDMA affected mGlu5 expression during neural precursor cell formation (group 1) and not during neural precursor differentiation (group 2). MDMA (450 µM) induced a significant increment in self-renewal properties in mESCs but did not reverse 2-methyl-6(phenylethynyl) pyridine (MPEP, 1 µM), a non-competitive selective mGlu5 antagonist. Fluorescence staining with anti-caspase 3 showed a significant increase in the number of apoptotic cells in the MDMA group. Conclusion: We observed a dual role for MDMA on mESCs: reduced proliferation and maintenance of self-renewal. The lack of decreasing stemness characteristic in presence of MPEP suggests that MDMA mediates its role through a different mechanism that requires further investigation. In

  18. [Adipose-derived stem cells promote the polarization from M1 macrophages to M2 macrophages].

    PubMed

    Yin, Xuehong; Pang, Chunyan; Bai, Li; Zhang, Ying; Geng, Lixia

    2016-03-01

    Objective To investigate the effects of adipose-derived stem cells (ADSCs) on M1/M2 macrophages and whether ADSCs are able to promote the polarization from M1 macrophages to M2 macrophages. Methods M1 macrophages were induced from J774.1 macrophages by 24-hour stimulation of lipopolysaccharide (LPS) and interferon γ (IFN-γ), and M2 macrophages were induced from J774.1 macrophages by interleukin 4 (IL-4) for another 24 hours. Then M1/M2 macrophages were separately cultured in the presence of ADSCs for 24 hours. The M1/M2 macrophages and their corresponding supernatants were collected for further analysis. The expressions of IL-6, tumor necrosis factor α (TNF-α), inducible nitric oxide synthase (iNOS), CC chemokine ligand 2 (CCL2), CD86, arginase 1 (Arg1), mannose receptors/CD206 (MR/CD206), IL-10, found in inflammatory zone 1 (FIZZ1), chitinase 3-like 3 (Ym-1) were detected by real-time PCR and ELISA. Results ADSCs significantly decreased the levels of IL-6, TNF-α, iNOS, CCL2 and CD86, and increased the levels of Arg1, CD206 and IL-10 in M1 macrophages. In the supernatant of M1 macrophages, the expressions of IL-6 and TNF-α were reduced, while those of CD206 were enhanced. In M2 macrophages, ADSCs resulted in down-regulation of IL-6, TNF-α, iNOS, CD86 and up-regulation of Arg1, CD206, FIZZ-1, Ym-1 and IL-10. In the supernatant of M2 macrophages, the expression levels of IL-6 and TNF-α were down-regulated and those of CD206 were up-regulated. Conclusion ADSCs can inhibit the gene expression of M1 macrophages and promote the gene expression of M2 macrophages, as well as mediate the polarization from M1 macrophages to M2 macrophages. PMID:26927552

  19. Wnt3a, a Protein Secreted by Mesenchymal Stem Cells Is Neuroprotective and Promotes Neurocognitive Recovery Following Traumatic Brain Injury.

    PubMed

    Zhao, Yuhai; Gibb, Stuart L; Zhao, Jing; Moore, Anthony N; Hylin, Michael J; Menge, Tyler; Xue, Hasen; Baimukanova, Gyulnar; Potter, Daniel; Johnson, Evan M; Holcomb, John B; Cox, Charles S; Dash, Pramod K; Pati, Shibani

    2016-05-01

    Intravenous administration of bone marrow derived mesenchymal stem cells (MSCs) has been shown to reduce blood brain barrier compromise and improve neurocognition following traumatic brain injury (TBI). These effects occur in the absence of engraftment and differentiation of these cells in the injured brain. Recent studies have shown that soluble factors produced by MSCs mediate a number of the therapeutic effects. In this study, we sought to determine if intravenous administration of MSCs (IV-MSCs) could enhance hippocampal neurogenesis following TBI. Our results demonstrate that IV-MSC treatment attenuates loss of neural stem cells and promotes hippocampal neurogenesis in TBI injured mice. As Wnt signaling has been implicated in neurogenesis, we measured circulating Wnt3a levels in serum following IV-MSC administration and found a significant increase in Wnt3a. Concurrent with this increase, we detected increased activation of the Wnt/β-catenin signaling pathway in hippocampal neurons. Furthermore, IV recombinant Wnt3a treatment provided neuroprotection, promoted neurogenesis, and improved neurocognitive function in TBI injured mice. Taken together, our results demonstrate a role for Wnt3a in the therapeutic potential of MSCs and identify Wnt3a as a potential stand-alone therapy or as part of a combination therapeutic strategy for the treatment of TBI. Stem Cells 2016;34:1263-1272. PMID:26840479

  20. Osteogenic differentiation of human mesenchymal stem cells promotes mineralization within a biodegradable peptide hydrogel.

    PubMed

    Castillo Diaz, Luis A; Elsawy, Mohamed; Saiani, Alberto; Gough, Julie E; Miller, Aline F

    2016-01-01

    An attractive strategy for the regeneration of tissues has been the use of extracellular matrix analogous biomaterials. Peptide-based fibrillar hydrogels have been shown to mimic the structure of extracellular matrix offering cells a niche to undertake their physiological functions. In this study, the capability of an ionic-complementary peptide FEFEFKFK (F, E, and K are phenylalanine, glutamic acid, and lysine, respectively) hydrogel to host human mesenchymal stem cells in three dimensions and induce their osteogenic differentiation is demonstrated. Assays showed sustained cell viability and proliferation throughout the hydrogel over 12 days of culture and these human mesenchymal stem cells differentiated into osteoblasts simply upon addition of osteogenic stimulation. Differentiated osteoblasts synthesized key bone proteins, including collagen-1 (Col-1), osteocalcin, and alkaline phosphatase. Moreover, mineralization occurred within the hydrogel. The peptide hydrogel is a naturally biodegradable material as shown by oscillatory rheology and reversed-phase high-performance liquid chromatography, where both viscoelastic properties and the degradation of the hydrogel were monitored over time, respectively. These findings demonstrate that a biodegradable octapeptide hydrogel can host and induce the differentiation of stem cells and has the potential for the regeneration of hard tissues such as alveolar bone. PMID:27493714

  1. Nukbone® promotes proliferation and osteoblastic differentiation of mesenchymal stem cells from human amniotic membrane

    SciTech Connect

    Rodríguez-Fuentes, Nayeli; Rodríguez-Hernández, Ana G.; Enríquez-Jiménez, Juana; Alcántara-Quintana, Luz E.; Fuentes-Mera, Lizeth; Piña-Barba, María C.; Zepeda-Rodríguez, Armando; and others

    2013-05-10

    Highlights: •Nukbone showed to be a good scaffold for adhesion, proliferation and differentiation of stem cells. •Nukbone induced osteoblastic differentiation of human mesenchymal stem cells. •Results showed that Nukbone offer an excellent option for bone tissue regeneration due to properties. -- Abstract: Bovine bone matrix Nukbone® (NKB) is an osseous tissue-engineering biomaterial that retains its mineral and organic phases and its natural bone topography and has been used as a xenoimplant for bone regeneration in clinics. There are not studies regarding its influence of the NKB in the behavior of cells during the repairing processes. The aim of this research is to demonstrate that NKB has an osteoinductive effect in human mesenchymal stem cells from amniotic membrane (AM-hMSCs). Results indicated that NKB favors the AM-hMSCs adhesion and proliferation up to 7 days in culture as shown by the scanning electron microscopy and proliferation measures using an alamarBlue assay. Furthermore, as demonstrated by reverse transcriptase polymerase chain reaction, it was detected that two gene expression markers of osteoblastic differentiation: the core binding factor and osteocalcin were higher for AM-hMSCs co-cultured with NKB in comparison with cultivated cells in absence of the biomaterial. As the results indicate, NKB possess the capability for inducing successfully the osteoblastic differentiation of AM-hMSC, so that, NKB is an excellent xenoimplant option for repairing bone tissue defects.

  2. Osteogenic differentiation of human mesenchymal stem cells promotes mineralization within a biodegradable peptide hydrogel

    PubMed Central

    Castillo Diaz, Luis A; Elsawy, Mohamed; Saiani, Alberto; Gough, Julie E; Miller, Aline F

    2016-01-01

    An attractive strategy for the regeneration of tissues has been the use of extracellular matrix analogous biomaterials. Peptide-based fibrillar hydrogels have been shown to mimic the structure of extracellular matrix offering cells a niche to undertake their physiological functions. In this study, the capability of an ionic-complementary peptide FEFEFKFK (F, E, and K are phenylalanine, glutamic acid, and lysine, respectively) hydrogel to host human mesenchymal stem cells in three dimensions and induce their osteogenic differentiation is demonstrated. Assays showed sustained cell viability and proliferation throughout the hydrogel over 12 days of culture and these human mesenchymal stem cells differentiated into osteoblasts simply upon addition of osteogenic stimulation. Differentiated osteoblasts synthesized key bone proteins, including collagen-1 (Col-1), osteocalcin, and alkaline phosphatase. Moreover, mineralization occurred within the hydrogel. The peptide hydrogel is a naturally biodegradable material as shown by oscillatory rheology and reversed-phase high-performance liquid chromatography, where both viscoelastic properties and the degradation of the hydrogel were monitored over time, respectively. These findings demonstrate that a biodegradable octapeptide hydrogel can host and induce the differentiation of stem cells and has the potential for the regeneration of hard tissues such as alveolar bone. PMID:27493714

  3. PEDF promotes self-renewal of limbal stem cell and accelerates corneal epithelial wound healing.

    PubMed

    Ho, Tsung-Chuan; Chen, Show-Li; Wu, Ju-Yun; Ho, Mei-Ying; Chen, Lee-Jen; Hsieh, Jui-Wen; Cheng, Huey-Chuan; Tsao, Yeou-Ping

    2013-09-01

    Limbal epithelial stem cell (LSC) transplantation is a prevalent therapeutic method for patients with LSC deficiency. The maintenance of stem cell characteristics in the process of culture expansion is critical for the success of ocular surface reconstruction. Pigment epithelial-derived factor (PEDF) increased the numbers of holoclone in LSC monolayer culture and preserved the stemness of LSC in suspension culture by evidence of ΔNp63α, Bmi-1, and ABCG2 expression. BrdU pulse-labeling assay also demonstrated that PEDF stimulated LSCs proliferation. In air-lift culture of limbal equivalent, PEDF was capable of increasing the numbers of ΔNp63α-positive cells. The mitogenic effect of PEDF was found to be mediated by the phosphorylations of p38 MAPK and STAT3 in LSCs. Synthetic 44-mer PEDF (residues 78-121) was as effective as the full length PEDF in LSC expansion in suspension culture and limbal equivalent formation, as well as the activation of p38 MAPK and STAT3. In mice subjecting to mechanical removal of cornea epithelium, 44-mer PEDF facilitated corneal wound healing. Microscopically, 44-mer PEDF advanced the early proliferative response in limbus, increased the proliferation of ΔNp63α-positive cells both in limbus and in epithelial healing front, and assisted the repopulation of limbus in the late phase of wound healing. In conclusion, the capability of expanding LSC in cell culture and in animal indicates the potential of PEDF and its fragment (e.g., 44-mer PEDF) in ameliorating limbal stem cell deficiency; and their uses as therapeutics for treating corneal wound. PMID:23553951

  4. Mesenchymal stem cells preconditioned with trimetazidine promote neovascularization of hearts under hypoxia/reoxygenation injury

    PubMed Central

    Hu, Xiaowu; Yang, Junjie; Wang, Ying; Zhang, You; Ii, Masaaki; Shen, Zhenya; Hui, Jie

    2015-01-01

    Background: Cell-based angiogenesis is a promising treatment for ischemic diseases; however, survival of implanted cells is impaired by the ischemic microenvironment. In this study, mesenchymal stem cells (MSCs) for cell transplantation were preconditioned with trimetazidine (TMZ). We hypothesized that TMZ enhances the survival rate of MSCs under hypoxic stimuli through up-regulation of HIF1-α. Methods and results: Bone marrow-derived rat mesenchymal stem cells were preconditioned with 10 μM TMZ for 6 h. TMZ preconditioning of MSCs remarkably increased cell viability and the expression of HIF1-α and Bcl-2, when cells were under hypoxia/reoxygenation (H/R) stimuli. But the protective effects of TMZ were abolished after knocking down of HIF-1α. Three days after implantation of the cells into the peri-ischemic zone of rat myocardial ischemia-reperfusion (I/R) injury model, survival of the TMZ-preconditioned MSCs was high. Furthermore, capillary density and cardiac function were significantly better in the rats implanted with TMZ-preconditioned MSCs 28 days after cell injection. Conclusions: TMZ preconditioning increased the survival rate of MSCs, through up-regulation of HIF1-α, thus contributing to neovascularization and improved cardiac function of rats subjected to myocardial I/R injury. PMID:26629255

  5. Cell-permeable p38 MAP kinase promotes migration of adult neural stem/progenitor cells

    PubMed Central

    Hamanoue, Makoto; Morioka, Kazuhito; Ohsawa, Ikuroh; Ohsawa, Keiko; Kobayashi, Masaaki; Tsuburaya, Kayo; Akasaka, Yoshikiyo; Mikami, Tetsuo; Ogata, Toru; Takamatsu, Ken

    2016-01-01

    Endogenous neural stem/progenitor cells (NPCs) can migrate toward sites of injury, but the migration activity of NPCs is insufficient to regenerate damaged brain tissue. In this study, we showed that p38 MAP kinase (p38) is expressed in doublecortin-positive adult NPCs. Experiments using the p38 inhibitor SB203580 revealed that endogenous p38 participates in NPC migration. To enhance NPC migration, we generated a cell-permeable wild-type p38 protein (PTD-p38WT) in which the HIV protein transduction domain (PTD) was fused to the N-terminus of p38. Treatment with PTD-p38WT significantly promoted the random migration of adult NPCs without affecting cell survival or differentiation; this effect depended on the cell permeability and kinase activity of the fusion protein. These findings indicate that PTD-p38WT is a novel and useful tool for unraveling the roles of p38, and that this protein provides a reasonable approach for regenerating the injured brain by enhancing NPC migration. PMID:27067799

  6. Neuron-like differentiation and selective ablation of undifferentiated embryonic stem cells containing suicide gene with Oct-4 promoter.

    PubMed

    Hara, Akira; Aoki, Hitomi; Taguchi, Ayako; Niwa, Masayuki; Yamada, Yasuhiro; Kunisada, Takahiro; Mori, Hideki

    2008-08-01

    In vivo transplantation of undifferentiated embryonic stem (ES) cells can produce teratomas with uncontrolled cell proliferation. Although ES cells may be attractive candidates for human cell-replacement therapy in the future, the major limitation of its application to the therapy is teratoma formation. In the present study, ES cells containing herpes simplex virus-thymidine kinase (HSV-tk) transgene for a suicide gene expression under the control of the Oct-4 promoter was used for ablation of undifferentiated ES cells, which may produce teratomas, using three-dimensional cell culture system allowing a multilayer cell construct. Selective ablation of undifferentiated ES cells expressing HSV-tk gene under the control of Oct-4 promoter was achieved by ganciclovir treatment. Surviving ES cells after ganciclovir treatment expressed several neuron-associated markers such as synaptophysin, beta-tubulin, vesicular glutamate transporter 1, syntaxin, protein kinase C and glial fibrillary acidic protein (GFAP) but not Oct-4. Coexpression of synaptophysin as a marker of neuronal synapse and GFAP as that of glial fibers in the surviving ES cells revealed finely structured neuronal network. Furthermore, decrease of Ki-67 proliferative index was detected in the surviving ES cells. In conclusion, selective ablation of undifferentiated ES cells by a suicide gene decreases proliferative activity and induces neuron-like differentiation in ES cells. PMID:18393636

  7. Laser biomodulation on stem cells

    NASA Astrophysics Data System (ADS)

    Liu, Timon C.; Duan, Rui; Li, Yan; Li, Xue-Feng; Tan, Li-Ling; Liu, Songhao

    2001-08-01

    Stem cells are views from the perspectives of their function, evolution, development, and cause. Counterintuitively, most stem cells may arise late in development, to act principally in tissue renewal, thus ensuring an organisms long-term survival. Surprisingly, recent reports suggest that tissue-specific adult stem cells have the potential to contribute to replenishment of multiple adult tissues. Stem cells are currently in the news for two reasons: the successful cultivation of human embryonic stem cell lines and reports that adult stem cells can differentiate into developmentally unrelated cell types, such as nerve cells into blood cells. The spotlight on stem cells has revealed gaps in our knowledge that must be filled if we are to take advantage of their full potential for treating devastating degenerative diseases such as Parkinsons's disease and muscular dystrophy. We need to know more about the intrinsic controls that keep stem cells as stem cells or direct them along particular differentiation pathways. Such intrinsic regulators are, in turn, sensitive to the influences of the microenvironment, or niche, where stem cells normally reside. Both intrinsic and extrinsic signals regular stem cell fate and some of these signals have now been identified. Vacek et al and Wang et al have studied the effect of low intensity laser on the haemopoietic stem cells in vitro. There experiments show there is indeed the effect of low intensity laser on the haemopoietic stem cells in vitro, and the present effect is the promotion of haemopoietic stem cells proliferation. In other words, low intensity laser irradiation can act as an extrinsic signal regulating stem cell fate. In this paper, we study how low intensity laser can be used to regulate stem cell fate from the viewpoint of collective phototransduction.

  8. Gain of BDNF Function in Engrafted Neural Stem Cells Promotes the Therapeutic Potential for Alzheimer's Disease.

    PubMed

    Wu, Cheng-Chun; Lien, Cheng-Chang; Hou, Wen-Hsien; Chiang, Po-Min; Tsai, Kuen-Jer

    2016-01-01

    Stem cell-based therapy is a potential treatment for neurodegenerative diseases, but its application to Alzheimer's disease (AD) remains limited. Brain-derived neurotrophic factor (BDNF) is critical in the pathogenesis and treatment of AD. Here, we present a novel therapeutic approach for AD treatment using BDNF-overexpressing neural stem cells (BDNF-NSCs). In vitro, BDNF overexpression was neuroprotective to beta-amyloid-treated NSCs. In vivo, engrafted BDNF-NSCs-derived neurons not only displayed the Ca(2+)-response fluctuations, exhibited electrophysiological properties of mature neurons and integrated into local brain circuits, but recovered the cognitive deficits. Furthermore, BDNF overexpression improved the engrafted cells' viability, neuronal fate, neurite complexity, maturation of electrical property and the synaptic density. In contrast, knockdown of the BDNF in BDNF-NSCs diminished stem cell-based therapeutic efficacy. Together, our findings indicate BDNF overexpression improves the therapeutic potential of engrafted NSCs for AD via neurogenic effects and neuronal replacement, and further support the feasibility of NSC-based ex vivo gene therapy for AD. PMID:27264956

  9. Stable CpG Hypomethylation of Adipogenic Promoters in Freshly Isolated, Cultured, and Differentiated Mesenchymal Stem Cells from Adipose Tissue

    PubMed Central

    Noer, Agate; Sørensen, Anita L.; Boquest, Andrew C.

    2006-01-01

    Mesenchymal stem cells from adipose tissue can differentiate into mesodermal lineages. Differentiation potential, however, varies between clones of adipose stem cells (ASCs), raising the hypothesis that epigenetic differences account for this variability. We report here a bisulfite sequencing analysis of CpG methylation of adipogenic (leptin [LEP], peroxisome proliferator-activated receptor gamma 2 [PPARG2], fatty acid-binding protein 4 [FABP4], and lipoprotein lipase [LPL]) promoters and of nonadipogenic (myogenin [MYOG], CD31, and GAPDH) loci in freshly isolated human ASCs and in cultured ASCs, in relation to gene expression and differentiation potential. Uncultured ASCs display hypomethylated adipogenic promoters, in contrast to myogenic and endothelial loci, which are methylated. Adipogenic promoters exhibit mosaic CpG methylation, on the basis of heterogeneous methylation between cells and of variation in the extent of methylation of a given CpG between donors, and both between and within clonal cell lines. DNA methylation reflects neither transcriptional status nor potential for gene expression upon differentiation. ASC culture preserves hypomethylation of adipogenic promoters; however, between- and within-clone mosaic methylation is detected. Adipogenic differentiation also maintains the overall CpG hypomethylation of LEP, PPARG2, FABP4, and LPL despite demethylation of specific CpGs and transcriptional induction. Furthermore, enhanced methylation at adipogenic loci in primary differentiated cells unrelated to adipogenesis argues for ASC specificity of the hypomethylated state of these loci. Therefore, mosaic hypomethylation of adipogenic promoters may constitute a molecular signature of ASCs, and DNA methylation does not seem to be a determinant of differentiation potential of these cells. PMID:16760426

  10. Suppression of ornithine decarboxylase promotes osteogenic differentiation of human bone marrow-derived mesenchymal stem cells.

    PubMed

    Tsai, Yo-Hsian; Lin, Kuan-Lian; Huang, Yuan-Pin; Hsu, Yi-Chiang; Chen, Chung-Hwan; Chen, Yuhsin; Sie, Min-Hua; Wang, Gwo-Jaw; Lee, Mon-Juan

    2015-07-22

    Ornithine decarboxylase (ODC) is the rate-limiting enzyme for polyamine biosynthesis. Suppression of ODC by its irreversible inhibitor, α-difluoromethylornithine (DFMO), or by RNA interference through siRNA, enhanced osteogenic gene expression and alkaline phosphatase activity, and accelerated matrix mineralization of human bone marrow-derived mesenchymal stem cells (hBMSCs). Besides, adipogenic gene expression and lipid accumulation was attenuated, indicating that the enhanced osteogenesis was accompanied by down-regulation of adipogenesis when ODC was suppressed. A decrease in the intracellular polyamine content of hBMSCs during osteogenic induction was observed, suggesting that the level of endogenous polyamines is regulated during differentiation of hBMSCs. This study elucidates the role of polyamine metabolism in the lineage commitment of stem cells and provides a potential new indication for DFMO as bone-stimulating drug. PMID:26140984

  11. The CCR4-NOT complex mediates deadenylation and degradation of stem cell mRNAs and promotes planarian stem cell differentiation.

    PubMed

    Solana, Jordi; Gamberi, Chiara; Mihaylova, Yuliana; Grosswendt, Stefanie; Chen, Chen; Lasko, Paul; Rajewsky, Nikolaus; Aboobaker, A Aziz

    2013-01-01

    Post-transcriptional regulatory mechanisms are of fundamental importance to form robust genetic networks, but their roles in stem cell pluripotency remain poorly understood. Here, we use freshwater planarians as a model system to investigate this and uncover a role for CCR4-NOT mediated deadenylation of mRNAs in stem cell differentiation. Planarian adult stem cells, the so-called neoblasts, drive the almost unlimited regenerative capabilities of planarians and allow their ongoing homeostatic tissue turnover. While many genes have been demonstrated to be required for these processes, currently almost no mechanistic insight is available into their regulation. We show that knockdown of planarian Not1, the CCR4-NOT deadenylating complex scaffolding subunit, abrogates regeneration and normal homeostasis. This abrogation is primarily due to severe impairment of their differentiation potential. We describe a stem cell specific increase in the mRNA levels of key neoblast genes after Smed-not1 knock down, consistent with a role of the CCR4-NOT complex in degradation of neoblast mRNAs upon the onset of differentiation. We also observe a stem cell specific increase in the frequency of longer poly(A) tails in these same mRNAs, showing that stem cells after Smed-not1 knock down fail to differentiate as they accumulate populations of transcripts with longer poly(A) tails. As other transcripts are unaffected our data hint at a targeted regulation of these key stem cell mRNAs by post-transcriptional regulators such as RNA-binding proteins or microRNAs. Together, our results show that the CCR4-NOT complex is crucial for stem cell differentiation and controls stem cell-specific degradation of mRNAs, thus providing clear mechanistic insight into this aspect of neoblast biology. PMID:24367277

  12. The CCR4-NOT Complex Mediates Deadenylation and Degradation of Stem Cell mRNAs and Promotes Planarian Stem Cell Differentiation

    PubMed Central

    Solana, Jordi; Gamberi, Chiara; Mihaylova, Yuliana; Grosswendt, Stefanie; Chen, Chen; Lasko, Paul; Rajewsky, Nikolaus; Aboobaker, A. Aziz

    2013-01-01

    Post-transcriptional regulatory mechanisms are of fundamental importance to form robust genetic networks, but their roles in stem cell pluripotency remain poorly understood. Here, we use freshwater planarians as a model system to investigate this and uncover a role for CCR4-NOT mediated deadenylation of mRNAs in stem cell differentiation. Planarian adult stem cells, the so-called neoblasts, drive the almost unlimited regenerative capabilities of planarians and allow their ongoing homeostatic tissue turnover. While many genes have been demonstrated to be required for these processes, currently almost no mechanistic insight is available into their regulation. We show that knockdown of planarian Not1, the CCR4-NOT deadenylating complex scaffolding subunit, abrogates regeneration and normal homeostasis. This abrogation is primarily due to severe impairment of their differentiation potential. We describe a stem cell specific increase in the mRNA levels of key neoblast genes after Smed-not1 knock down, consistent with a role of the CCR4-NOT complex in degradation of neoblast mRNAs upon the onset of differentiation. We also observe a stem cell specific increase in the frequency of longer poly(A) tails in these same mRNAs, showing that stem cells after Smed-not1 knock down fail to differentiate as they accumulate populations of transcripts with longer poly(A) tails. As other transcripts are unaffected our data hint at a targeted regulation of these key stem cell mRNAs by post-transcriptional regulators such as RNA-binding proteins or microRNAs. Together, our results show that the CCR4-NOT complex is crucial for stem cell differentiation and controls stem cell-specific degradation of mRNAs, thus providing clear mechanistic insight into this aspect of neoblast biology. PMID:24367277

  13. HIF-1 regulates CD47 expression in breast cancer cells to promote evasion of phagocytosis and maintenance of cancer stem cells

    PubMed Central

    Zhang, Huimin; Lu, Haiquan; Xiang, Lisha; Bullen, John W.; Zhang, Chuanzhao; Samanta, Debangshu; Gilkes, Daniele M.; He, Jianjun; Semenza, Gregg L.

    2015-01-01

    Increased expression of CD47 has been reported to enable cancer cells to evade phagocytosis by macrophages and to promote the cancer stem cell phenotype, but the molecular mechanisms regulating CD47 expression have not been determined. Here we report that hypoxia-inducible factor 1 (HIF-1) directly activates transcription of the CD47 gene in hypoxic breast cancer cells. Knockdown of HIF activity or CD47 expression increased the phagocytosis of breast cancer cells by bone marrow-derived macrophages. CD47 expression was increased in mammosphere cultures, which are enriched for cancer stem cells, and CD47 deficiency led to cancer stem cell depletion. Analysis of datasets derived from thousands of patients with breast cancer revealed that CD47 expression was correlated with HIF target gene expression and with patient mortality. Thus, CD47 expression contributes to the lethal breast cancer phenotype that is mediated by HIF-1. PMID:26512116

  14. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus.

    PubMed

    Zhu, Fei-Bin; Fang, Xiang-Jing; Liu, De-Wu; Shao, Ying; Zhang, Hong-Yan; Peng, Yan; Zhong, Qing-Ling; Li, Yong-Tie; Liu, De-Ming

    2016-03-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 days. With prolonged time, type I collagen content gradually increased, yet type III collagen content gradually diminished. Abundant protein gene product 9.5- and substance P-immunoreactive nerve fibers regenerated. Partial nerve fiber endings extended to the epidermis. The therapeutic effects of combined substance P and epidermal stem cells were better than with amniotic membrane and either factor alone. Our results suggest that the combination of substance P and epidermal stem cells effectively contributes to nerve regeneration and wound healing in diabetic rats. PMID:27127492

  15. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus

    PubMed Central

    Zhu, Fei-bin; Fang, Xiang-jing; Liu, De-wu; Shao, Ying; Zhang, Hong-yan; Peng, Yan; Zhong, Qing-ling; Li, Yong-tie; Liu, De-ming

    2016-01-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 days. With prolonged time, type I collagen content gradually increased, yet type III collagen content gradually diminished. Abundant protein gene product 9.5- and substance P-immunoreactive nerve fibers regenerated. Partial nerve fiber endings extended to the epidermis. The therapeutic effects of combined substance P and epidermal stem cells were better than with amniotic membrane and either factor alone. Our results suggest that the combination of substance P and epidermal stem cells effectively contributes to nerve regeneration and wound healing in diabetic rats. PMID:27127492

  16. miR-30 family promotes migratory and invasive abilities in CD133(+) pancreatic cancer stem-like cells.

    PubMed

    Tsukasa, Koichiro; Ding, Qiang; Miyazaki, Yumi; Matsubara, Shyuichiro; Natsugoe, Shoji; Takao, Sonshin

    2016-07-01

    Pancreatic cancer is a deadly disease with a poor prognosis. Recently, miRNAs have been reported to be abnormally expressed in several cancers and play a role in cancer development and progression. However, the role of miRNA in cancer stem cells remains unclear. Therefore, our aim was to investigate the role of miRNA in the CD133(+) pancreatic cancer cell line Capan-1M9 because CD133 is a putative marker of pancreatic cancer stem cells. Using miRNA microarray, we found that the expression level of the miR-30 family decreased in CD133 genetic knockdown shCD133 Capan-1M9 cells. We focused on miR-30a, -30b, and -30c in the miR-30 family and created pancreatic cancer cell sublines, each transfected with these miRNAs. High expression of miR-30a, -30b, or -30c had no effect on cell proliferation and sphere forming. In contrast, these sublines were resistant to gemcitabine, which is a standard anticancer drug for pancreatic cancer, and in addition, promoted migration and invasion. Moreover, mesenchymal markers were up-regulated by these miRNAs, suggesting that mesenchymal phenotype is associated with an increase in migration and invasion. Thus, our study demonstrated that high expression of the miR-30 family modulated by CD133 promotes migratory and invasive abilities in CD133(+) pancreatic cancer cells. These findings suggest that targeted therapies to the miR-30 family contribute to the development of novel therapies for CD133(+) pancreatic cancer stem cells. PMID:26965588

  17. Histone modifications and p53 binding poise the p21 promoter for activation in human embryonic stem cells

    PubMed Central

    Itahana, Yoko; Zhang, Jinqiu; Göke, Jonathan; Vardy, Leah A.; Han, Rachel; Iwamoto, Kozue; Cukuroglu, Engin; Robson, Paul; Pouladi, Mahmoud A.; Colman, Alan; Itahana, Koji

    2016-01-01

    The high proliferation rate of embryonic stem cells (ESCs) is thought to arise partly from very low expression of p21. However, how p21 is suppressed in ESCs has been unclear. We found that p53 binds to the p21 promoter in human ESCs (hESCs) as efficiently as in differentiated human mesenchymal stem cells, however it does not promote p21 transcription in hESCs. We observed an enrichment for both the repressive histone H3K27me3 and activating histone H3K4me3 chromatin marks at the p21 locus in hESCs, suggesting it is a suppressed, bivalent domain which overrides activation by p53. Reducing H3K27me3 methylation in hESCs rescued p21 expression, and ectopic expression of p21 in hESCs triggered their differentiation. Further, we uncovered a subset of bivalent promoters bound by p53 in hESCs that are similarly induced upon differentiation in a p53-dependent manner, whereas p53 promotes the transcription of other target genes which do not show an enrichment of H3K27me3 in ESCs. Our studies reveal a unique epigenetic strategy used by ESCs to poise undesired p53 target genes, thus balancing the maintenance of pluripotency in the undifferentiated state with a robust response to differentiation signals, while utilizing p53 activity to maintain genomic stability and homeostasis in ESCs. PMID:27346849

  18. Histone modifications and p53 binding poise the p21 promoter for activation in human embryonic stem cells.

    PubMed

    Itahana, Yoko; Zhang, Jinqiu; Göke, Jonathan; Vardy, Leah A; Han, Rachel; Iwamoto, Kozue; Cukuroglu, Engin; Robson, Paul; Pouladi, Mahmoud A; Colman, Alan; Itahana, Koji

    2016-01-01

    The high proliferation rate of embryonic stem cells (ESCs) is thought to arise partly from very low expression of p21. However, how p21 is suppressed in ESCs has been unclear. We found that p53 binds to the p21 promoter in human ESCs (hESCs) as efficiently as in differentiated human mesenchymal stem cells, however it does not promote p21 transcription in hESCs. We observed an enrichment for both the repressive histone H3K27me3 and activating histone H3K4me3 chromatin marks at the p21 locus in hESCs, suggesting it is a suppressed, bivalent domain which overrides activation by p53. Reducing H3K27me3 methylation in hESCs rescued p21 expression, and ectopic expression of p21 in hESCs triggered their differentiation. Further, we uncovered a subset of bivalent promoters bound by p53 in hESCs that are similarly induced upon differentiation in a p53-dependent manner, whereas p53 promotes the transcription of other target genes which do not show an enrichment of H3K27me3 in ESCs. Our studies reveal a unique epigenetic strategy used by ESCs to poise undesired p53 target genes, thus balancing the maintenance of pluripotency in the undifferentiated state with a robust response to differentiation signals, while utilizing p53 activity to maintain genomic stability and homeostasis in ESCs. PMID:27346849

  19. Electroacupuncture in the repair of spinal cord injury: inhibiting the Notch signaling pathway and promoting neural stem cell proliferation

    PubMed Central

    Geng, Xin; Sun, Tao; Li, Jing-hui; Zhao, Ning; Wang, Yong; Yu, Hua-lin

    2015-01-01

    Electroacupuncture for the treatment of spinal cord injury has a good clinical curative effect, but the underlying mechanism is unclear. In our experiments, the spinal cord of adult Sprague-Dawley rats was clamped for 60 seconds. Dazhui (GV14) and Mingmen (GV4) acupoints of rats were subjected to electroacupuncture. Enzyme-linked immunosorbent assay revealed that the expression of serum inflammatory factors was apparently downregulated in rat models of spinal cord injury after electroacupuncture. Hematoxylin-eosin staining and immunohistochemistry results demonstrated that electroacupuncture contributed to the proliferation of neural stem cells in rat injured spinal cord, and suppressed their differentiation into astrocytes. Real-time quantitative PCR and western blot assays showed that electroacupuncture inhibited activation of the Notch signaling pathway induced by spinal cord injury. These findings indicate that electroacupuncture repaired the injured spinal cord by suppressing the Notch signaling pathway and promoting the proliferation of endogenous neural stem cells. PMID:25878587

  20. Differentiation of rabbit bone mesenchymal stem cells into endothelial cells in vitro and promotion of defective bone regeneration in vivo.

    PubMed

    Liu, Jinzhong; Liu, Chao; Sun, Bin; Shi, Ce; Qiao, Chunyan; Ke, Xiaoliang; Liu, Shutai; Liu, Xia; Sun, Hongchen

    2014-04-01

    Tissue engineering strategies often fail to regenerate bones because of inadequate vascularization, especially in the reconstruction of large segmental bone defects. Large volumes of vascular endothelial cells (ECs) that functionally interact with osteoblasts during osteogenesis are difficult to obtain. In this study, we simulated bone healing by co-culturing differentiated ECs and mesenchymal stem cells (MSCs) either on a culture plate or on a polylactide glycolic acid (PLGA) scaffold in vitro. We also evaluated the effect of osteogenesis in repairing rabbit mandible defects in vivo. In this study, MSCs were separated from rabbit as the seed cells. After passage, the MSCs were cultured in an EC-conditioned medium to differentiate into ECs. Immunohistochemical staining analysis with CD34 showed that the induced cells had the characteristics of ECs and MSC. The induced ECs were co-cultured in vitro, and the induction of MSCs to osteoblast served as the control. Alkaline phosphatase (ALP) and alizarin red (AZR) staining experiments were performed, and the Coomassie brilliant blue total protein and ALP activity were measured. The MSCs proliferated and differentiated into osteoblast-like cells through direct contact between the derived ECs and MSCs. The co-cultured cells were seeded on PLGA scaffold to repair 1 cm mandible defects in the rabbit. The effectiveness of the repairs was assessed through soft X-ray and histological analyses. The main findings indicated that MSCs survived well on the scaffold and that the scaffold is biocompatible and noncytotoxic. The results demonstrated that the co-cultured MSC-derived ECs improved MSC osteogenesis and promoted new bone formation. This study may serve as a basis for the use of in vitro co-culturing techniques as an improvisation to bone tissue engineering for the repair of large bone defects. PMID:23943083

  1. TAp63 prevents premature aging by promoting adult stem cell maintenance

    PubMed Central

    Su, Xiaohua; Paris, Maryline; Gi, Young Jin; Tsai, Kenneth Y.; Cho, Min Soon; Lin, Yu-Li; Biernaskie, Jeffrey A.; Sinha, Satrajit; Prives, Carol; Pevny, Larysa H.; Miller, Freda D.; Flores, Elsa R.

    2012-01-01

    SUMMARY The cellular mechanisms that regulate the maintenance of adult tissue stem cells are still largely unknown. We show here that the p53 family member, TAp63, is essential for maintenance of epidermal and dermal precursors and that, in its absence, these precursors senesce and skin ages prematurely. Specifically, we have developed a TAp63 conditional knockout mouse and used it to ablate TAp63 in the germline (TAp63−/−) or in K14-expressing cells in the basal layer of the epidermis (TAp63fl/fl;K14cre+). TAp63−/− mice age prematurely and develop blisters, skin ulcerations, senescence of hair follicle-associated dermal and epidermal cells, and decreased hair morphogenesis. These phenotypes are likely due to loss of TAp63 in dermal and epidermal precursors since both cell types show defective proliferation, early senescence, and genomic instability. These data indicate that TAp63 serves to maintain adult skin stem cells by regulating cellular senescence and genomic stability, thereby preventing premature tissue aging. PMID:19570515

  2. Tg737 inhibition results in malignant transformation in fetal liver stem/progenitor cells by promoting cell-cycle progression and differentiation arrest.

    PubMed

    You, Nan; Liu, Weihui; Zhong, Xiao; Ji, Ru; Zhang, Ming; You, Houcheng; Dou, Kefeng; Tao, Kaishan

    2012-08-01

    Cancer stem/progenitor cells (CSPCs) may originate from the malignant transformation of normal stem cells. However, the mechanism by which normal stem cells undergo such transformation is not understood. Our previous studies provided evidence that Tg737 may play an important role in carcinogenesis of liver stem cells. In this study, we investigated the role of Tg737 in the malignant transformation of fetal liver stem/progenitor cells (FLSPCs). We inhibited Tg737 in FLSPCs using short hairpin RNA (shRNA). The microscopic observations of freshly purified Tg737 normal FLSPCs (nFLSPCs) and Tg737-silent FLSPCs (sFLSPCs), which showed high expression levels of stem cell markers, revealed no significant morphological changes in sFLSPCs. Following RNAi of Tg737, the mRNA and protein levels of sFLSPCs decreased by 81.81% and 80.10% as shown by PCR, Western blot and immunocytochemistry analyses. Excluding apoptosis-related effects, we found that silencing of Tg737 resulted in enhanced cell proliferation through promoting cell-cycle progression via upregulation of cyclin D1 and cyclin B expression (P < 0.05). Silencing of Tg737 also resulted in significant arrest of cell differentiation (P < 0.05), stable expression of both albumin (ALB) and alpha fetoprotein (AFP) (P > 0.05) and quiescent ultrastructure. Assessment of cell malignant traits by transwell migration assays and by growth of xenograft tumors in athymic mice showed that reduced expression of Tg737 greatly promoted cell invasion and hepatocarcinogenesis of FLSPCs (P < 0.05). This work shows that inactivation of Tg737 may play an important role in malignant transformation of FLSPCs. PMID:21837759

  3. Long-Duration Three-Dimensional Spheroid Culture Promotes Angiogenic Activities of Adipose-Derived Mesenchymal Stem Cells.

    PubMed

    Lee, Jun Hee; Han, Yong-Seok; Lee, Sang Hun

    2016-05-01

    Mesenchymal stem cells (MSCs) offer significant therapeutic promise for various regenerative therapies. However, MSC-based therapy for injury exhibits low efficacy due to the pathological environment in target tissues and the differences between in vitro and in vivo conditions. To address this issue, we developed adipose-derived MSC spheroids as a novel delivery method to preserve the stem cell microenvironment. MSC spheroids were generated by suspension culture for 3 days, and their sizes increased in a time-dependent manner. After re-attachment of MSC spheroids to the plastic dish, their adhesion capacity and morphology were not altered. MSC spheroids showed enhanced production of hypoxia-induced angiogenic cytokines such as vascular endothelial growth factor (VEGF), stromal cell derived factor (SDF), and hepatocyte growth factor (HGF). In addition, spheroid culture promoted the preservation of extracellular matrix (ECM) components, such as laminin and fibronectin, in a culture time- and spheroid size-dependent manner. Furthermore, phosphorylation of AKT, a cell survival signal, was significantly higher and the expression of pro-apoptotic molecules, poly (ADP ribose) polymerase-1 (PARP-1) and cleaved caspase-3, was markedly lower in the spheroids than in MSCs in monolayers. In the murine hindlimb ischemia model, transplanted MSC spheroids showed better proliferation than MSCs in monolayer. These findings suggest that MSC spheroids promote MSC bioactivities via secretion of angiogenic cytokines, preservation of ECM components, and regulation of apoptotic signals. Therefore, MSC spheroid-based cell therapy may serve as a simple and effective strategy for regenerative medicine. PMID:26869524

  4. Long-Duration Three-Dimensional Spheroid Culture Promotes Angiogenic Activities of Adipose-Derived Mesenchymal Stem Cells

    PubMed Central

    Lee, Jun Hee; Han, Yong-Seok; Lee, Sang Hun

    2016-01-01

    Mesenchymal stem cells (MSCs) offer significant therapeutic promise for various regenerative therapies. However, MSC-based therapy for injury exhibits low efficacy due to the pathological environment in target tissues and the differences between in vitro and in vivo conditions. To address this issue, we developed adipose-derived MSC spheroids as a novel delivery method to preserve the stem cell microenvironment. MSC spheroids were generated by suspension culture for 3 days, and their sizes increased in a time-dependent manner. After re-attachment of MSC spheroids to the plastic dish, their adhesion capacity and morphology were not altered. MSC spheroids showed enhanced production of hypoxia-induced angiogenic cytokines such as vascular endothelial growth factor (VEGF), stromal cell derived factor (SDF), and hepatocyte growth factor (HGF). In addition, spheroid culture promoted the preservation of extracellular matrix (ECM) components, such as laminin and fibronectin, in a culture time- and spheroid size-dependent manner. Furthermore, phosphorylation of AKT, a cell survival signal, was significantly higher and the expression of pro-apoptotic molecules, poly (ADP ribose) polymerase-1 (PARP-1) and cleaved caspase-3, was markedly lower in the spheroids than in MSCs in monolayers. In the murine hindlimb ischemia model, transplanted MSC spheroids showed better proliferation than MSCs in monolayer. These findings suggest that MSC spheroids promote MSC bioactivities via secretion of angiogenic cytokines, preservation of ECM components, and regulation of apoptotic signals. Therefore, MSC spheroid-based cell therapy may serve as a simple and effective strategy for regenerative medicine. PMID:26869524

  5. Involvement of Wnt/β-catenin signaling in the mesenchymal stem cells promote metastatic growth and chemoresistance of cholangiocarcinoma

    PubMed Central

    Yuan, Jiahui; Yan, Congcong; Hu, Shaoping; Tong, Yinping; Mao, Yubin; Hu, Tianhui; Zhang, Bing; Song, Gang

    2015-01-01

    Mesenchymal stem cells (MSCs) are multi-potent progenitor cells with ability to differentiate into multiple lineages, including bone, cartilage, fat, and muscles. Recent research indicates that MSCs can be efficiently recruited to tumor sites, modulating tumor growth and metastasis. However, the underlying molecular mechanisms are not fully understood. Here, we first demonstrated that human umbilical cord-derived mesenchymal stem cells (hUC-MSCs), when mixed with human cholangiocarcinoma cell lines QBC939 in a xenograft tumor model, significantly increased the cancer cells proliferation and metastatic potency. MSCs and their conditioned media (MSC-CM) could improve the drug resistance of tumor when the compound K (CK) as an anti-cancer drug, a major intestinal bacterial metabolite of panaxoside, was administered to xenograft tumor mice. Furthermore, MSCs greatly increased the colony formation and invasion of cholangiocarcinoma cells QBC939 and Mz-ChA-1. Immunochemistry studies of cholangiocarcinoma tissue chips and transplantation tumor from nude mice showed that the expression of β-catenin was important for cholangiocarcinoma development. We further demonstrated that MSCs and MSCs-CM could promote proliferation and migration of cholangiocarcinoma cells through targeting the Wnt/β-catenin signaling pathway. hUC-MSCs or MSCs-CM stimulated Wnt activity by promoting the nuclear translocation of β-catenin, and up-regulated Wnt target genes MMPs family, cyclin D1 and c-Myc. Together, our studies highlight a critical role for MSCs on cancer metastasis and indicate MSCs promote metastatic growth and chemoresistance of cholangiocarcinoma cells via activation of Wnt/β-catenin signaling. PMID:26474277

  6. Layered double hydroxide nanoparticles promote self-renewal of mouse embryonic stem cells through the PI3K signaling pathway

    NASA Astrophysics Data System (ADS)

    Wu, Youjun; Zhu, Rongrong; Zhou, Yang; Zhang, Jun; Wang, Wenrui; Sun, Xiaoyu; Wu, Xianzheng; Cheng, Liming; Zhang, Jing; Wang, Shilong

    2015-06-01

    Embryonic stem cells (ESCs) hold great potential for regenerative medicine due to their two unique characteristics: self-renewal and pluripotency. Several groups of nanoparticles have shown promising applications in directing the stem cell fate. Herein, we investigated the cellular effects of layered double hydroxide nanoparticles (LDH NPs) on mouse ESCs (mESCs) and the associated molecular mechanisms. Mg-Al-LDH NPs with an average diameter of ~100 nm were prepared by hydrothermal methods. To determine the influences of LDH NPs on mESCs, cellular cytotoxicity, self-renewal, differentiation potential, and the possible signaling pathways were explored. Evaluation of cell viability, lactate dehydrogenase release, ROS generation and apoptosis demonstrated the low cytotoxicity of LDH NPs. The alkaline phosphatase activity and the expression of pluripotency genes in mESCs were examined, which indicated that exposure to LDH NPs could support self-renewal and inhibit spontaneous differentiation of mESCs under feeder-free culture conditions. The self-renewal promotion was further proved to be independent of the leukemia inhibitory factor (LIF). Furthermore, cells treated with LDH NPs maintained the potential to differentiate into all three germ layers both in vitro and in vivo through formation of embryoid bodies and teratomas. In addition, we observed that LDH NPs initiated the activation of the PI3K/Akt pathway, while treatment with the PI3K inhibitor LY294002 could block the effects of LDH NPs on mESCs. The results confirmed that the promotion of self-renewal by LDH NPs was associated with activation of the PI3K/Akt signaling pathway. Altogether, our studies identified a new role of LDH NPs in maintaining self-renewal of mouse ES cells which could potentially be applied in stem cell research.Embryonic stem cells (ESCs) hold great potential for regenerative medicine due to their two unique characteristics: self-renewal and pluripotency. Several groups of nanoparticles

  7. Icariin promotes cell proliferation and regulates gene expression in human neural stem cells in vitro.

    PubMed

    Yang, Pan; Guan, Yun-Qian; Li, Ya-Li; Zhang, Li; Zhang, Lan; Li, Lin

    2016-08-01

    Icariin (ICA), which is an essential bioactive component extracted from the herb Epimedium, possesses neuroprotective properties. The aim of the present study was to investigate the regulatory roles of ICA in cell proliferation and gene expression in human neural stem cells (NSCs) in vitro. Single cells were isolated from the corpus striatum of 16‑20‑week human fetuses obtained following spontaneous abortion. The cells were cultured in Dulbecco's modified Eagle's medium/F12 complete medium and were characterized by immunostaining and cell differentiation assay. NSCs were treated with ICA, and cell proliferation was assessed using the Cell Counting kit‑8 cell proliferation assay kit. In addition, neurosphere formation was comparatively studied between the ICA‑treated and control cells. cDNA microarray analysis was performed to examine the effects of ICA on gene expression. Altered expression of genes important for regulating NSC proliferation was further analyzed by quantitative polymerase chain reaction (qPCR). The results demonstrated that typical neurospheres appeared after 7‑10 days of culturing of individual cells isolated from the corpus striatum. These cells expressed nestin, an important NSC marker, and in the presence of differentiation medium they expressed β‑III‑tubulin, a specific neuronal marker, and glial fibrillary acidic protein, an astrocyte marker. Treatment with ICA enhanced NSC proliferation and the formation of neurospheres. Microarray data and pathway analysis revealed that the genes regulated by ICA were involved in several signaling pathways, including the Wnt and basic fibroblast growth factor (bFGF) pathways, which are important for the regulation of NSC function. Upregulation of frizzled class receptor 7 and dishevelled segment polarity protein 3, which are key players in the Wnt pathway, and fibroblast growth factor receptor 1, which is the receptor for bFGF, and downregulation of glycogen synthase kinase‑3β, which

  8. FoxM1 Promotes Stemness and Radio-Resistance of Glioblastoma by Regulating the Master Stem Cell Regulator Sox2

    PubMed Central

    Kim, Dong Geon; Cho, Hee Jin; Kim, Yeonghwan; Rheey, Jinguen; Shin, Kayoung; Seo, Yun Jee; Choi, Yeon-Sook; Lee, Jung-Il; Lee, Jeongwu; Joo, Kyeung Min; Nam, Do-Hyun

    2015-01-01

    Glioblastoma (GBM) is the most aggressive and most lethal brain tumor. As current standard therapy consisting of surgery and chemo-irradiation provides limited benefit for GBM patients, novel therapeutic options are urgently required. Forkhead box M1 (FoxM1) transcription factor is an oncogenic regulator that promotes the proliferation, survival, and treatment resistance of various human cancers. The roles of FoxM1 in GBM remain incompletely understood, due in part to pleotropic nature of the FoxM1 pathway. Here, we show the roles of FoxM1 in GBM stem cell maintenance and radioresistance. ShRNA-mediated FoxM1 inhibition significantly impeded clonogenic growth and survival of patient-derived primary GBM cells with marked downregulation of Sox2, a master regulator of stem cell phenotype. Ectopic expression of Sox2 partially rescued FoxM1 inhibition-mediated effects. Conversely, FoxM1 overexpression upregulated Sox2 expression and promoted clonogenic growth of GBM cells. These data, with a direct binding of FoxM1 in the Sox2 promoter region in GBM cells, suggest that FoxM1 regulates stemness of primary GBM cells via Sox2. We also found significant increases in FoxM1 and Sox2 expression in GBM cells after irradiation both in vitro and in vivo orthotopic tumor models. Notably, genetic or a small-molecule FoxM1 inhibitor-mediated FoxM1 targeting significantly sensitized GBM cells to irradiation, accompanying with Sox2 downregulation. Finally, FoxM1 inhibition combined with irradiation in a patient GBM-derived orthotopic model significantly impeded tumor growth and prolonged the survival of tumor bearing mice. Taken together, these results indicate that the FoxM1-Sox2 signaling axis promotes clonogenic growth and radiation resistance of GBM, and suggest that FoxM1 targeting combined with irradiation is a potentially effective therapeutic approach for GBM. PMID:26444992

  9. Low level light promotes the proliferation and differentiation of bone marrow derived mesenchymal stem cells

    NASA Astrophysics Data System (ADS)

    Ahn, Jin-Chul; Rhee, Yun-Hee; Choi, Sun-Hyang; Kim, Dae Yu; Chung, Phil-Sang

    2015-03-01

    Low-level light irradiation (LLLI) reported to stimulate the proliferation or differentiation of a variety of cell types. However, very little is known about the effect of light therapy on stem cells. The aim of the present study was to evaluate the effect of LLLI on the molecular physiological change of human bone marrow derived stem cells (hBMSC) by wavelength (470, 630, 660, 740 and 850, 50mW). The laser diode was performed with different time interval (0, 7.5, 15, 30J/cm2, 50mW) on hBMSC. To determine the molecular physiological changes of cellular level of hBMSC, the clonogenic assay, ATP assay, reactive oxygen species (ROS) detection, mitochondria membrane potential (MMPΦ) staining and calcium efflux assay were assessed after irradiation. There was a difference between with and without irradiation on hBMSCs. An energy density up to 30 J/cm² improved the cell proliferation in comparison to the control group. Among these irradiated group, 630 and 660nm were significantly increased the cell proliferation. The cellular level of ATP and calcium influx was increased with energy dose-dependent in all LLLI groups. Meanwhile, ROS and MMPΦ were also increased after irradiation except 470nm. It can be concluded that LLLI using infrared light and an energy density up to 30 J/cm² has a positive stimulatory effect on the proliferation or differentiation of hBMSCs. Our results suggest that LLLI may influence to the mitochondrial membrane potential activity through ATP synthesis and increased cell metabolism which leads to cell proliferation and differentiation.

  10. Inhibiting PPARγ by erythropoietin while upregulating TAZ by IGF1 synergistically promote osteogenic differentiation of mesenchymal stem cells.

    PubMed

    Zhou, Jianwei; Wei, Fangyuan; Ma, Yuquan

    2016-09-01

    Erythropoietin (EPO) is reported to promote osteogenesis and inhibit adipogenesis of mesenchymal stem cells (MSC) through inhibiting PPARγ, while insulin-like growth factor 1 (IGF1) is able to enhance osteogenesis via upregulating transcriptional coactivator with PDZ-binding motif (TAZ). The different targets of EPO and IGF1 suggested their potential synergism to enhance osteogenesis. In this study, we aimed to determine the potential synergism of EPO and IGF1 and its efficacy on MSC differentiation. Rat adipose-derived mesenchymal stem cells (ADSCs) were separately treated with EPO, IGF1 and EPO/IGF1. It was observed that the co-treatment using EPO and IGF1 was able to potently promote the osteogenic differentiation of rat ADSCs compared with EPO or IGF1 alone, which offered a promising effective option to strengthen bone tissue regeneration for bone defects. Further, we demonstrated that the enhanced osteogenic differentiation by EPO and IGF1 co-treatment was almost counteracted by activating PPARγ through PPARγ agonist, RSG, and blocking TAZ through TAZ silencing RNA, siTAZ. Thus, it could be concluded that EPO and IGF1 possessed a potent synergism in promoting osteogenic differentiation, and the synergism was mainly attributed to co-regulation of different osteogenic regulators PPARγ and TAZ, which were targeted genes of EPO and IGF1 respectively. PMID:27422606

  11. [Present status of research in bone marrow-derived mesenchymal stem cells for promoting the healing of diabetic ulcer].

    PubMed

    Zheng, Shu-Juan; Jia, Chi-Yu

    2012-08-01

    The delayed healing of diabetic ulcer has been haunting the surgeons and researchers for a long time. Although we have been researching and exploring the effective therapies for many years, the progress has been limited. Bone marrow-derived mesenchymal stem cells (BMSCs) have gradually won worldwide attention for their characteristics of differentiating into tissue repair cells and secreting multiple cytokines as well as growth factors. In recent years, the role of BMSCs in the treatment of diabetic ulcer has been drawing more and more attention. This article reviewed the advancement in the research of BMSCs in promoting the healing of diabetic ulcer. Through a discussion of the treatment of diabetic ulcer, the related research in BMSCs, as well as its role in diabetic ulcer treatment, the mechanism of BMSCs in promoting healing of diabetic ulcers is discussed. We expect through further research, unified criteria for the quality of BMSCs, application approach and dosage of BMSCs could be established. PMID:23248965

  12. Chinese herbs and their active ingredients for activating xue (blood) promote the proliferation and differentiation of neural stem cells and mesenchymal stem cells

    PubMed Central

    2014-01-01

    Some Chinese herbs are anti-thrombolysis, and anti-inflammatory, improves brain RNA content, promotes brain protein synthesis, enhances dopamine function, regulates brain hormones, and improves microcirculation in central nervous system that might improve, repair and rehabilitation from the stroke and brain injury. Specific Chinese herbs and their components, such as Acanthopanax, Angelica, could maintain the survival of neural stem cells, and Rhodiola, Ganoderma spore Polygala, Tetramethylpyrazine, Gardenia, Astragaloside and Ginsenoside Rg1 promoted proliferation of neural stem cells, and Rhodiola, Astragaloside promoted differentiation of neural stem cell into neuron and glia in vivo. Astragalus, Safflower, Musk, Baicalin, Geniposide, Ginkgolide B, Cili polysaccharide, Salidroside, Astragaloside, Antler polypeptides, Ginsenoside Rg1, Panax notoginseng saponins promoted proliferation and differentiation of neural stem cells in vitro. Salvia, Astragalus, Ginsenoside Rg1, P. notoginseng saponins, Musk polypeptide, Muscone and Ginkgolide B promoted neural-directed differentiation of MSCs into nerve cells. These findings are encouraging further research into the Chinese herbs for developing drugs in treating patients of stroke and brain injury. PMID:24716802

  13. A fetal human heart cardiac-inducing RNA (CIR) promotes the differentiation of stem cells into cardiomyocytes.

    PubMed

    Kochegarov, Andrei; Moses-Arms, Ashley; Lemanski, Larry F

    2015-08-01

    A specific human fetal heart RNA has been discovered, which has the ability to induce myocardial cell formation from mouse embryonic and human-induced pluripotent stem cells in culture. In this study, commercially obtained RNA from human fetal heart was cloned, sequenced, and synthesized using standard laboratory approaches. Molecular analyses of the specific fetal cardiac-inducing RNA (CIR), revealed that it is a fragment of N-sulfoglucosaminesulfohydrolase and the caspase recruitment domain family member 14 precursor. Stem cells transfected with CIRs often form into spindle-shaped cells characteristic of cardiomyocytes,and express the cardiac-specific contractile protein marker, troponin-T, in addition to tropomyosin and α-actinin as detected by immunohistochemical staining. Expression of these contractile proteins showed organization into sarcomeric myofibrils characteristic of striated cardiac muscle cells. Computer analyses of the RNA secondary structures of the active CIR show significant similarities to a RNA from salamander or myofibril-inducing RNA (MIR), which also promotes non-muscle cells to differentiate into cardiac muscle. Thus, these two RNAs, salamander MIR and the newly discovered human-cloned CIR reported here, appear to have evolutionarily conserved secondary structures suggesting that both play major roles in vertebrate heart development and, particularly, in the differentiation of cardiomyocytes from non-muscle cells during development. PMID:25761723

  14. Arsenic trioxide disrupts glioma stem cells via promoting PML degradation to inhibit tumor growth

    PubMed Central

    Zhou, Wenchao; Cheng, Lin; Shi, Yu; Ke, Susan Q.; Huang, Zhi; Fang, Xiaoguang; Chu, Cheng-wei; Xie, Qi; Bian, Xiu-wu; Rich, Jeremy N.; Bao, Shideng

    2015-01-01

    Glioblastoma multiforme (GBM) is the most lethal brain tumor. Tumor relapse in GBM is inevitable despite maximal therapeutic interventions. Glioma stem cells (GSCs) have been found to be critical players in therapeutic resistance and tumor recurrence. Therapeutic drugs targeting GSCs may significantly improve GBM treatment. In this study, we demonstrated that arsenic trioxide (As2O3) effectively disrupted GSCs and inhibited tumor growth in the GSC-derived orthotopic xenografts by targeting the promyelocytic leukaemia (PML). As2O3 treatment induced rapid degradation of PML protein along with severe apoptosis in GSCs. Disruption of the endogenous PML recapitulated the inhibitory effects of As2O3 treatment on GSCs both in vitro and in orthotopic tumors. Importantly, As2O3 treatment dramatically reduced GSC population in the intracranial GBM xenografts and increased the survival of mice bearing the tumors. In addition, As2O3 treatment preferentially inhibited cell growth of GSCs but not matched non-stem tumor cells (NSTCs). Furthermore, As2O3 treatment or PML disruption potently diminished c-Myc protein levels through increased poly-ubiquitination and proteasome degradation of c-Myc. Our study indicated a potential implication of As2O3 in GBM treatment and highlighted the important role of PML/c-Myc axis in the maintenance of GSCs. PMID:26510911

  15. Biochanin A Promotes Osteogenic but Inhibits Adipogenic Differentiation: Evidence with Primary Adipose-Derived Stem Cells

    PubMed Central

    Su, Shu-Jem; Su, Shu-Hui; Shyu, Huey-Wen; Chen, Kuan-Ming; Yeh, Hua

    2013-01-01

    Biochanin A has promising effects on bone formation in vivo, although the underlying mechanism remains unclear yet. This study therefore aimed to investigate whether biochanin A regulates osteogenic and adipogenic differentiation using primary adipose-derived stem cells. The effects of biochanin A (at a physiologically relevant concentration of 0.1–1 μM) were assessed in vitro using various approaches, including Oil red O staining, Nile red staining, alizarin red S staining, alkaline phosphatase (ALP) activity, flow cytometry, RT-PCR, and western blotting. The results showed that biochanin A significantly suppressed adipocyte differentiation, as demonstrated by the inhibition of cytoplasmic lipid droplet accumulation, along with the inhibition of peroxisome proliferator-activated receptor gamma (PPARγ), lipoprotein lipase (LPL), and leptin and osteopontin (OPN) mRNA expression, in a dose-dependent manner. On the other hand, treatment of cells with 0.3 μM biochanin A increased the mineralization and ALP activity, and stimulated the expression of the osteogenic marker genes ALP and osteocalcin (OCN). Furthermore, biochanin A induced the expression of runt-related transcription factor 2 (Runx2), osteoprotegerin (OPG), and Ras homolog gene family, member A (RhoA) proteins. These observations suggest that biochanin A prevents adipogenesis, enhances osteoblast differentiation in mesenchymal stem cells, and has beneficial regulatory effects in bone formation. PMID:23843885

  16. Promotion of Cortical Neurogenesis from the Neural Stem Cells in the Adult Mouse Subcallosal Zone.

    PubMed

    Kim, Joo Yeon; Choi, Kyuhyun; Shaker, Mohammed R; Lee, Ju-Hyun; Lee, Boram; Lee, Eunsoo; Park, Jae-Yong; Lim, Mi-Sun; Park, Chang-Hwan; Shin, Ki Soon; Kim, Hyun; Geum, Dongho; Sun, Woong

    2016-04-01

    Neurogenesis occurs spontaneously in the subventricular zone (SVZ) of the lateral ventricle in adult rodent brain, but it has long been debated whether there is sufficient adult neurogenesis in human SVZ. Subcallosal zone (SCZ), a posterior continuum of SVZ closely associated with posterior regions of cortical white matter, has also been reported to contain adult neural stem cells (aNSCs) in both rodents and humans. However, little is known whether SCZ-derived aNSC (SCZ-aNSCs) can produce cortical neurons following brain injury. We found that SCZ-aNSCs exhibited limited neuronal differentiation potential in culture and after transplantation in mice. Neuroblasts derived from SCZ initially migrated toward injured cortex regions following brain injury, but later exhibited apoptosis. Overexpression of anti-apoptotic bcl-xL in the SCZ by retroviral infection rescued neuroblasts from cell death in the injured cortex, but neuronal maturation was still limited, resulting in atrophy. In combination with Bcl-xL, infusion of brain-derived neurotropic factor rescued atrophy, and importantly, a subset of such SCZ-aNSCs differentiated and attained morphological and physiological characteristics of mature, excitatory neurons. These results suggest that the combination of anti-apoptotic and neurotrophic factors might enable the use of aNSCs derived from the SCZ in cortical neurogenesis for neural replacement therapy. Stem Cells 2016;34:888-901. PMID:26701067

  17. The RUNX1 +24 enhancer and P1 promoter identify a unique subpopulation of hematopoietic progenitor cells derived from human pluripotent stem cells

    PubMed Central

    Ferrell, Patrick I; Xi, Jiafei; Ma, Chao; Adlakha, Mitali; Kaufman, Dan S.

    2016-01-01

    Derivation of hematopoietic stem cells from human pluripotent stem cells remains a key goal for the fields of developmental biology and regenerative medicine. Here, we use a novel genetic reporter system to prospectively identify and isolate early hematopoietic cells derived from human embryonic stem cells (hESCs) and human induced pluripotent cells (iPSCs). Cloning the human RUNX1c P1 promoter and +24 enhancer to drive expression of tdTomato (tdTom) in hESCs and iPSCs, we demonstrate that tdTom expression faithfully enriches for RUNX1c-expressing hematopoietic progenitor cells. Time-lapse microscopy demonstrated the tdTom+ hematopoietic cells to emerge from adherent cells. Furthermore, inhibition of primitive hematopoiesis by blocking Activin/Nodal signaling promoted the expansion and/or survival of tdTom+ population. Notably, RUNX1c/tdTom+ cells represent only a limited subpopuation of CD34+CD45+ and CD34+CD43+ cells with a unique genetic signature. Using gene array analysis, we find significantly lower expression of Let-7 and mir181a microRNAs in the RUNX1c/tdTom+ cell population. These phenotypic and genetic analyses comparing the RUNX1c/tdTom+ population to CD34+CD45+ umbilical cord blood and fetal liver demonstrate several key differences that likely impact the development of HSCs capable of long-term multilineage engraftment from hESCs and iPSCs. PMID:25546363

  18. Repeated lipopolysaccharide stimulation promotes cellular senescence in human dental pulp stem cells (DPSCs).

    PubMed

    Feng, Xingmei; Feng, Guijuan; Xing, Jing; Shen, Biyu; Tan, Wei; Huang, Dan; Lu, Xiaohui; Tao, Tao; Zhang, Jinlong; Li, Liren; Gu, Zhifeng

    2014-05-01

    Dental pulp stem cells (DPSCs) are a type of mesenchymal stem cell (MSC) characterized by multi-lineage differentiation making it an attractive choice for tissue regeneration. However, before DPSCs can be used for cell-based therapy, we have to understand their biological properties in response to intrinsic and extrinsic stimuli such as lipopolysaccharide (LPS). DPSCs were therefore stimulated with LPS and senescence was evaluated by senescence-associated β-galactosidase (SA-β-gal) staining, with cell number and cell-cycle arrest being examined by BrdU assay and flow cytometry, respectively. The morphology of DPSCs was characterized by their flat shape, increased size and increased SA-β-gal activity after repeated stimulation (3 or 6 times) with LPS. Reactive oxygen species (ROS) staining showed that the number of ROS-stained cells and the DCFH fluorescent level were higher in the LPS-treated DPSCs compared with those in the untreated DPSCs. Protein and mRNA expression levels of γ-H2A.X and p16(INK4A) were also increased in DPSCs with repeated LPS stimulation. We found that the LPS bound with Toll-like receptor 4 (TLR4) and that TLR4 signaling accounted for p16(INK4A) expression. Further results indicated that the senescence of DPSCs stimulated repeatedly with LPS was reversed by p16(INK4A) short interfering RNA. The DNA damage response and p16(INK4A) pathways might be the main mediators of DPSC senescence induced by repeated LPS stimulation. Thus, DPSCs tend to undergo senescence after repeated activation, implying that DPSC senescence starts after many inflammatory challenges. Ultimately, these findings should lead to a better understanding of DPSC-based clinical therapy. PMID:24676500

  19. Leptin as a mediator of tumor-stromal interactions promotes breast cancer stem cell activity.

    PubMed

    Giordano, Cinzia; Chemi, Francesca; Panza, Salvatore; Barone, Ines; Bonofiglio, Daniela; Lanzino, Marilena; Cordella, Angela; Campana, Antonella; Hashim, Adnan; Rizza, Pietro; Leggio, Antonella; Győrffy, Balázs; Simões, Bruno M; Clarke, Robert B; Weisz, Alessandro; Catalano, Stefania; Andò, Sebastiano

    2016-01-12

    Breast cancer stem cells (BCSCs) play crucial roles in tumor initiation, metastasis and therapeutic resistance. A strict dependency between BCSCs and stromal cell components of tumor microenvironment exists. Thus, novel therapeutic strategies aimed to target the crosstalk between activated microenvironment and BCSCs have the potential to improve clinical outcome. Here, we investigated how leptin, as a mediator of tumor-stromal interactions, may affect BCSC activity using patient-derived samples (n = 16) and breast cancer cell lines, and determined the potential benefit of targeting leptin signaling in these model systems. Conditioned media (CM) from cancer-associated fibroblasts and breast adipocytes significantly increased mammosphere formation in breast cancer cells and depletion of leptin from CM completely abrogated this effect. Mammosphere cultures exhibited increased leptin receptor (OBR) expression and leptin exposure enhanced mammosphere formation. Microarray analyses revealed a similar expression profile of genes involved in stem cell biology among mammospheres treated with CM and leptin. Interestingly, leptin increased mammosphere formation in metastatic breast cancers and expression of OBR as well as HSP90, a target of leptin signaling, were directly correlated with mammosphere formation in metastatic samples (r = 0.68/p = 0.05; r = 0.71/p = 0.036, respectively). Kaplan-Meier survival curves indicated that OBR and HSP90 expression were associated with reduced overall survival in breast cancer patients (HR = 1.9/p = 0.022; HR = 2.2/p = 0.00017, respectively). Furthermore, blocking leptin signaling by using a full leptin receptor antagonist significantly reduced mammosphere formation in breast cancer cell lines and patient-derived samples. Our results suggest that leptin/leptin receptor signaling may represent a potential therapeutic target that can block the stromal-tumor interactions driving BCSC-mediated disease progression. PMID:26556856

  20. Therapeutic angiogenesis promotes efficacy of human umbilical cord matrix stem cell transplantation in cardiac repair

    PubMed Central

    Moradi, Kaveh; Abbasi, Mehdi; Aboulhasani, Farid; Abbasi, Niloufar; Babatunde, Kehinde Adebayo; Sargolzaeiaval, Fereydoon; Dehpour, Ahmad-Reza

    2015-01-01

    Objective(s): Although previous studies have confirmed the beneficial effects of human umbilical cord matrix stem cell (hUCM) transplantation post myocardial infarction (MI), but this stem cell resource has no potential to induce angiogenesis. In order to achieve the process of angiogenesis and cardiomyocyte regeneration, two required factors for cardiac repair agents were examined namely; hUCM and VEGF on an infarcted heart. The main objective of this research is to investigate the combinatory effect of dhUCM and VEGF transplantation on an infarcted heart. Materials and Methods: 45 min of ligating the left anterior descending coronary artery, the MI-induced animals received 50 μl PBS, 5 μg VEGF, 5×106 hUCM cells alone, combined with 5 μg VEGF and 5×106 differentiated hUCM cells alone or combined with 5 μg VEGF through intramyocardial injection. MI group, without hUCM and VEGF served as the control group. Left ventricular function and angiogenesis were also evaluated. Results: After eight weeks post MI, there were significant rise in left ventricular ejection farction in dhUCM+VEGF group compared to the other treated and non-treated groups (P<0.05). Fibrosis tissue was markedly lower in the dhUCM+VEGF and hUCM+VEGF groups compared to the other treated and non-treated groups (P<0.05). Despite these benefits, vascular density in dhUCM+VEGF group was not markedly different compared to VEGF and hUCM+VEGF groups. The transplanted hUCM and dhUCM cells survived and migrated to the infarcted area. Conclusion: Our findings demonstrated that the dhUCM cells transplantation combined with VEGF were more efficient on an infarcted heart. PMID:26221480

  1. Three RNA Binding Proteins Form a Complex to Promote Differentiation of Germline Stem Cell Lineage in Drosophila

    PubMed Central

    Zhao, Shaowei; Geng, Qing; Gao, Yu; Li, Xin; Zhang, Yang; Wang, Zhaohui

    2014-01-01

    In regenerative tissues, one of the strategies to protect stem cells from genetic aberrations, potentially caused by frequent cell division, is to transiently expand the stem cell daughters before further differentiation. However, failure to exit the transit amplification may lead to overgrowth, and the molecular mechanism governing this regulation remains vague. In a Drosophila mutagenesis screen for factors involved in the regulation of germline stem cell (GSC) lineage, we isolated a mutation in the gene CG32364, which encodes a putative RNA-binding protein (RBP) and is designated as tumorous testis (tut). In tut mutant, spermatogonia fail to differentiate and over-amplify, a phenotype similar to that in mei-P26 mutant. Mei-P26 is a TRIM-NHL tumor suppressor homolog required for the differentiation of GSC lineage. We found that Tut binds preferentially a long isoform of mei-P26 3′UTR, and is essential for the translational repression of mei-P26 reporter. Bam and Bgcn are both RBPs that have also been shown to repress mei-P26 expression. Our genetic analyses indicate that tut, bam, or bgcn is required to repress mei-P26 and to promote the differentiation of GSCs. Biochemically, we demonstrate that Tut, Bam, and Bgcn can form a physical complex in which Bam holds Tut on its N-terminus and Bgcn on its C-terminus. Our in vivo and in vitro evidence illustrate that Tut acts with Bam, Bgcn to accurately coordinate proliferation and differentiation in Drosophila germline stem cell lineage. PMID:25412508

  2. Mechanical Stimulation of Mesenchymal Stem Cell Proliferation and Differentiation Promotes Osteogenesis While Preventing Dietary-Induced Obesity

    PubMed Central

    Luu, Yen Kim; Capilla, Encarnacion; Rosen, Clifford J; Gilsanz, Vicente; Pessin, Jeffrey E; Judex, Stefan; Rubin, Clinton T

    2009-01-01

    Mesenchymal stem cells (MSCs) are defined by their ability to self-renew and differentiate into the cells that form mesodermal tissues such as bone and fat. Low magnitude mechanical signals (LMMS) have been shown to be anabolic to bone and have been recently reported to suppress the development of fat in normal animals fed a regular diet. Using male C57BL/6J mice, the ability of LMMS (0.2g, 90-Hz signal applied for 15 min/d, 5 d/wk) to simultaneously promote bone formation and prevent diet-induced obesity was correlated to mechanical influences on the molecular environment of the bone marrow, as indicated by the population dynamics and lineage commitment of MSCs. Six weeks of LMMS increased the overall marrow-based stem cell population by 37% and the number of MSCs by 46%. Concomitant with the increase in stem cell number, the differentiation potential of MSCs in the bone marrow was biased toward osteoblastic and against adipogenic differentiation, as reflected by upregulation of the transcription factor Runx2 by 72% and downregulation of PPARγ by 27%. The phenotypic impact of LMMS on MSC lineage determination was evident at 14 wk, where visceral adipose tissue formation was suppressed by 28%, whereas trabecular bone volume fraction in the tibia was increased by 11%. Translating this to the clinic, a 1-yr trial in young women (15–20 yr; n = 48) with osteopenia showed that LMMS increased trabecular bone in the spine and kept visceral fat at baseline levels, whereas control subjects showed no change in BMD, yet an increase in visceral fat. Mechanical modulation of stem cell proliferation and differentiation indicates a unique therapeutic target to aid in tissue regeneration and repair and may represent the basis of a nonpharmacologic strategy to simultaneously prevent obesity and osteoporosis. PMID:18715135

  3. Adult human dental pulp stem cells promote blood-brain barrier permeability through vascular endothelial growth factor-a expression.

    PubMed

    Winderlich, Joshua N; Kremer, Karlea L; Koblar, Simon A

    2016-06-01

    Stem cell therapy is a promising new treatment option for stroke. Intravascular administration of stem cells is a valid approach as stem cells have been shown to transmigrate the blood-brain barrier. The mechanism that causes this effect has not yet been elucidated. We hypothesized that stem cells would mediate localized discontinuities in the blood-brain barrier, which would allow passage into the brain parenchyma. Here, we demonstrate that adult human dental pulp stem cells express a soluble factor that increases permeability across an in vitro model of the blood-brain barrier. This effect was shown to be the result of vascular endothelial growth factor-a. The effect could be amplified by exposing dental pulp stem cell to stromal-derived factor 1, which stimulates vascular endothelial growth factor-a expression. These findings support the use of dental pulp stem cell in therapy for stroke. PMID:26661186

  4. Three-Dimensional Adult Cardiac Extracellular Matrix Promotes Maturation of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes.

    PubMed

    Fong, Ashley H; Romero-López, Mónica; Heylman, Christopher M; Keating, Mark; Tran, David; Sobrino, Agua; Tran, Anh Q; Pham, Hiep H; Fimbres, Cristhian; Gershon, Paul D; Botvinick, Elliot L; George, Steven C; Hughes, Christopher C W

    2016-08-01

    Pluripotent stem cell-derived cardiomyocytes (CMs) have great potential in the development of new therapies for cardiovascular disease. In particular, human induced pluripotent stem cells (iPSCs) may prove especially advantageous due to their pluripotency, their self-renewal potential, and their ability to create patient-specific cell lines. Unfortunately, pluripotent stem cell-derived CMs are immature, with characteristics more closely resembling fetal CMs than adult CMs, and this immaturity has limited their use in drug screening and cell-based therapies. Extracellular matrix (ECM) influences cellular behavior and maturation, as does the geometry of the environment-two-dimensional (2D) versus three-dimensional (3D). We therefore tested the hypothesis that native cardiac ECM and 3D cultures might enhance the maturation of iPSC-derived CMs in vitro. We demonstrate that maturation of iPSC-derived CMs was enhanced when cells were seeded into a 3D cardiac ECM scaffold, compared with 2D culture. 3D cardiac ECM promoted increased expression of calcium-handling genes, Junctin, CaV1.2, NCX1, HCN4, SERCA2a, Triadin, and CASQ2. Consistent with this, we find that iPSC-derived CMs in 3D adult cardiac ECM show increased calcium signaling (amplitude) and kinetics (maximum upstroke and downstroke) compared with cells in 2D. Cells in 3D culture were also more responsive to caffeine, likely reflecting an increased availability of calcium in the sarcoplasmic reticulum. Taken together, these studies provide novel strategies for maturing iPSC-derived CMs that may have applications in drug screening and transplantation therapies to treat heart disease. PMID:27392582

  5. Human carcinoma-associated mesenchymal stem cells promote ovarian cancer chemotherapy resistance via a BMP4/HH signaling loop

    PubMed Central

    Coffman, Lan G.; Choi, Yun-Jung; McLean, Karen; Allen, Benjamin L.; di Magliano, Marina Pasca; Buckanovich, Ronald J.

    2016-01-01

    The tumor microenvironment is critical to cancer growth and therapy resistance. We previously characterized human ovarian carcinoma-associated mesenchymal stem cells (CA-MSCs). CA-MSCs are multi-potent cells that can differentiate into tumor microenvironment components including fibroblasts, myofibroblasts and adipocytes. We previously reported CA-MSCs, compared to normal MSCs, express high levels of BMP proteins and promote tumor growth by increasing numbers of cancer stem-like cells (CSCs). We demonstrate here that ovarian tumor cell-secreted Hedgehog (HH) induces CA-MSC BMP4 expression. CA-MSC-derived BMP4 reciprocally increases ovarian tumor cell HH expression indicating a positive feedback loop. Interruption of this loop with a HH pathway inhibitor or BMP4 blocking antibody decreases CA-MSC-derived BMP4 and tumor-derived HH preventing enrichment of CSCs and reversing chemotherapy resistance. The impact of HH inhibition was only seen in CA-MSC-containing tumors, indicating the importance of a humanized stroma. These results are reciprocal to findings in pancreatic and bladder cancer, suggesting HH signaling effects are tumor tissue specific warranting careful investigation in each tumor type. Collectively, we define a critical positive feedback loop between CA-MSC-derived BMP4 and ovarian tumor cell-secreted HH and present evidence for the further investigation of HH as a clinical target in ovarian cancer. PMID:26755648

  6. Relief of hypoxia by angiogenesis promotes neural stem cell differentiation by targeting glycolysis.

    PubMed

    Lange, Christian; Turrero Garcia, Miguel; Decimo, Ilaria; Bifari, Francesco; Eelen, Guy; Quaegebeur, Annelies; Boon, Ruben; Zhao, Hui; Boeckx, Bram; Chang, Junlei; Wu, Christine; Le Noble, Ferdinand; Lambrechts, Diether; Dewerchin, Mieke; Kuo, Calvin J; Huttner, Wieland B; Carmeliet, Peter

    2016-05-01

    Blood vessels are part of the stem cell niche in the developing cerebral cortex, but their in vivo role in controlling the expansion and differentiation of neural stem cells (NSCs) in development has not been studied. Here, we report that relief of hypoxia in the developing cerebral cortex by ingrowth of blood vessels temporo-spatially coincided with NSC differentiation. Selective perturbation of brain angiogenesis in vessel-specific Gpr124 null embryos, which prevented the relief from hypoxia, increased NSC expansion at the expense of differentiation. Conversely, exposure to increased oxygen levels rescued NSC differentiation in Gpr124 null embryos and increased it further in WT embryos, suggesting that niche blood vessels regulate NSC differentiation at least in part by providing oxygen. Consistent herewith, hypoxia-inducible factor (HIF)-1α levels controlled the switch of NSC expansion to differentiation. Finally, we provide evidence that high glycolytic activity of NSCs is required to prevent their precocious differentiation in vivo Thus, blood vessel function is required for efficient NSC differentiation in the developing cerebral cortex by providing oxygen and possibly regulating NSC metabolism. PMID:26856890

  7. Bone marrow-derived mesenchymal stem cell-secreted IL-8 promotes the angiogenesis and growth of colorectal cancer

    PubMed Central

    Cai, Jianye; Shi, Jianqiang; Sui, Xin; Cao, Yong; Huang, Weijun; Chen, Xiaoyong; Cai, Zijie; Li, Hongyu; Bardeesi, Adham Sameer A.; Zhang, Bin; Liu, Muyun; Song, Wu; Wang, Maosheng; Xiang, Andy Peng

    2015-01-01

    Mesenchymal stem cells (MSCs) have recently been shown to home to tumors and contribute to the formation of the tumor-associated stroma. In addition, MSCs can secrete paracrine factors to facilitate tumor progression. However, the involvement of MSC-derived cytokines in colorectal cancer (CRC) angiogenesis and growth has not been clearly addressed. In this study, we report that interleukin-8 (IL-8) was the most highly upregulated pro-angiogenic factor in MSCs co-cultured with CRC cells and was expressed at substantially higher levels in MSCs than CRC cells. To evaluate the effect of MSC-derived IL-8 on CRC angiogenesis and growth, we used MSCs that expressed small hairpin (interfering) RNAs (shRNA) targeting IL-8 (shIL-8-MSCs). We found that MSC-secreted IL-8 promoted human umbilical vein endothelial cell (HUVEC) proliferation and migration, tube-formation ability and CRC cell proliferation. Additionally, in vivo studies showed that MSCs promoted tumor angiogenesis partially through IL-8. Taken together, these findings suggest that IL-8 secreted by MSCs promotes CRC angiogenesis and growth and can therefore serve as a potential novel therapeutic target. PMID:26517517

  8. Homeobox B7 promotes the osteogenic differentiation potential of mesenchymal stem cells by activating RUNX2 and transcript of BSP

    PubMed Central

    Gao, Run-Tao; Zhan, Li-Ping; Meng, Cen; Zhang, Ning; Chang, Shi-Min; Yao, Rui; Li, Chong

    2015-01-01

    Mesenchymal stem cells (MSCs) are a reliable cell source for tissue regeneration. However, the molecular mechanisms underlying the directed differentiation of MSCs remain unclear; thus, their use is limited. Here, we investigate HOXB7 function in the osteogenic differentiation potentials of MSCs using stem cells from apical papilla (SCAPs) and bone marrow stem cells (BMSCs). The HOXB7 gene is highly expressed in BMSCs compared with dental tissue-derived MSCs. We found that, in vitro, over-expression of HOXB7 in SCAPs enhanced alkaline phosphatase (ALP) activity and mineralization. HOXB7 over-expression affected the mRNA expression of osteonectin (ON), collagen alpha-2(I) chain (COL1A2), bone sialoprotein (BSP), and osteocalcin (OCN), led to the expression of the key transcription factor, runt-related transcription factor 2 (RUNX2), and promoted SCAP osteogenic differentiation in vitro. The knock-down of HOXB7 inhibited ALP activity, mineralization, and the expression of ON, BSP, COL1A2, OCN, and RUNX2 in BMSCs in vitro. In addition, transplant experiments in nude mice confirmed that SCAP osteogenesis was triggered when HOXB7 was activated. Furthermore, Over-expression of HOXB7 significantly increased the levels of HOXB7 associated with the BSP promoter by ChIP assays. Taken together, these results indicate that HOXB7 enhances SCAP osteogenic differentiation by up-regulating RUNX2 and directly activating transcript of BSP. Thus, the activation of HOXB7 signaling might improve tissue regeneration mediated by MSCs. These results provide insight into the mechanism underlying the directed differentiation of MSCs. PMID:26379836

  9. Alteration of protein prenylation promotes spermatogonial differentiation and exhausts spermatogonial stem cells in newborn mice

    PubMed Central

    Diao, Fan; Jiang, Chen; Wang, Xiu-Xing; Zhu, Rui-Lou; Wang, Qiang; Yao, Bing; Li, Chao-Jun

    2016-01-01

    Spermatogenesis in adulthood depends on the successful neonatal establishment of the spermatogonial stem cell (SSC) pool and gradual differentiation during puberty. The stage-dependent changes in protein prenylation in the seminiferous epithelium might be important during the first round of spermatogenesis before sexual maturation, but the mechanisms are unclear. We have previous found that altered prenylation in Sertoli cells induced spermatogonial apoptosis in the neonatal testis, resulting in adult infertility. Now we further explored the role of protein prenylation in germ cells, using a conditional deletion of geranylgeranyl diphosphate synthase (Ggpps) in embryonic stage and postmeiotic stage respectively. We observed infertility of Ggpps−/− Ddx4-Cre mice that displayed a Sertoli-cell-only syndrome phenotype, which resulted from abnormal spermatogonial differentiation and SSC depletion during the prepubertal stage. Analysis of morphological characteristics and cell-specific markers revealed that spermatogonial differentiation was enhanced from as early as the 7th postnatal day in the first round of spermatogenesis. Studies of the molecular mechanisms indicated that Ggpps deletion enhanced Rheb farnesylation, which subsequently activated mTORC1 and facilitated spermatogonial differentiation. In conclusion, the prenylation balance in germ cells is crucial for spermatogonial differentiation fate decision during the prepubertal stage, and the disruption of this process results in primary infertility. PMID:27374985

  10. Promotion of Cancer Stem-Like Cell Properties in Hepatitis C Virus-Infected Hepatocytes

    PubMed Central

    Kwon, Young-Chan; Bose, Sandip K.; Steele, Robert; Meyer, Keith; Di Bisceglie, Adrian M.; Ray, Ratna B.

    2015-01-01

    ABSTRACT We have previously reported that hepatitis C virus (HCV) infection of primary human hepatocytes (PHH) induces the epithelial mesenchymal transition (EMT) state and extends hepatocyte life span (S. K. Bose, K. Meyer, A. M. Di Bisceglie, R. B. Ray, and R. Ray, J Virol 86:13621–13628, 2012, http://dx.doi.org/10.1128/JVI.02016-12). These hepatocytes displayed sphere formation on ultralow binding plates and survived for more than 12 weeks. The sphere-forming hepatocytes expressed a number of cancer stem-like cell (CSC) markers, including high levels of the stem cell factor receptor c-Kit. The c-Kit receptor is regarded as one of the CSC markers in hepatocellular carcinoma (HCC). Analysis of c-Kit mRNA displayed a significant increase in the liver biopsy specimens of chronically HCV-infected patients. We also found c-Kit is highly expressed in transformed human hepatocytes (THH) infected in vitro with cell culture-grown HCV genotype 2a. Further studies suggested that HCV core protein significantly upregulates c-Kit expression at the transcriptional level. HCV infection of THH led to a significant increase in the number of spheres displayed on ultralow binding plates and in enhanced EMT and CSC markers and tumor growth in immunodeficient mice. The use of imatinib or dasatinib as a c-Kit inhibitor reduced the level of sphere-forming cells in culture. The sphere-forming cells were sensitive to treatment with sorafenib, a multikinase inhibitor, that is used for HCC treatment. Further, stattic, an inhibitor of the Stat3 molecule, induced sphere-forming cell death. A combination of sorafenib and stattic had a significantly stronger effect, leading to cell death. These results suggested that HCV infection potentiates CSC generation, and selected drugs can be targeted to efficiently inhibit cell growth. IMPORTANCE HCV infection may develop into HCC as an end-stage liver disease. We focused on understanding the mechanism for the risk of HCC from chronic HCV infection

  11. ΔNp63 promotes stem cell activity in mammary gland development and basal-like breast cancer by enhancing Fzd7 expression and Wnt signaling

    PubMed Central

    Chakrabarti, Rumela; Wei, Yong; Hwang, Julie; Hang, Xiang; Blanco, Mario Andres; Choudhury, Abrar; Tiede, Benjamin; Romano, Rose-Anne; DeCoste, Christina; Mercatali, Laura; Ibrahim, Toni; Amadori, Dino; Kannan, Nagarajan; Eaves, Connie J; Sinha, Satrajit; Kang, Yibin

    2014-01-01

    Emerging evidence suggests that cancer is populated and maintained by tumor initiating cells (TICs) with stem-like properties similar to that of adult tissue stem cells. Despite recent advances, the molecular regulatory mechanisms that may be shared between normal and malignant stem cells remain poorly understood. Here we show that the ΔNp63 isoform of the Trp63 transcription factor promotes normal mammary stem cell (MaSC) activity by increasing the expression of the Wnt receptor Fzd7, thereby enhancing Wnt signaling. Importantly, Fzd7-dependent enhancement of Wnt signaling by ΔNp63 also governs tumor initiating activity of the basal subtype of breast cancer. These findings establish ΔNp63 as a key regulator of stem cells in both normal and malignant mammary tissues and provide direct evidence that breast cancer TICs and normal MaSCs share common regulatory mechanisms. PMID:25241036

  12. Dexamethasone and Azathioprine Promote Cytoskeletal Changes and Affect Mesenchymal Stem Cell Migratory Behavior

    PubMed Central

    Schneider, Natália; Gonçalves, Fabiany da Costa; Pinto, Fernanda Otesbelgue; Lopez, Patrícia Luciana da Costa; Araújo, Anelise Bergmann; Pfaffenseller, Bianca; Passos, Eduardo Pandolfi; Cirne-Lima, Elizabeth Obino; Meurer, Luíse; Lamers, Marcelo Lazzaron; Paz, Ana Helena

    2015-01-01

    Glucocorticoids and immunosuppressive drugs are commonly used to treat inflammatory disorders, such as inflammatory bowel disease (IBD), and despite a few improvements, the remission of IBD is still difficult to maintain. Due to their immunomodulatory properties, mesenchymal stem cells (MSCs) have emerged as regulators of the immune response, and their viability and activation of their migratory properties are essential for successful cell therapy. However, little is known about the effects of immunosuppressant drugs used in IBD treatment on MSC behavior. The aim of this study was to evaluate MSC viability, nuclear morphometry, cell polarity, F-actin and focal adhesion kinase (FAK) distribution, and cell migratory properties in the presence of the immunosuppressive drugs azathioprine (AZA) and dexamethasone (DEX). After an initial characterization, MSCs were treated with DEX (10 μM) or AZA (1 μM) for 24 hrs or 7 days. Neither drug had an effect on cell viability or nuclear morphometry. However, AZA treatment induced a more elongated cell shape, while DEX was associated with a more rounded cell shape (P < 0.05) with a higher presence of ventral actin stress fibers (P < 0.05) and a decrease in protrusion stability. After 7 days of treatment, AZA improved the cell spatial trajectory (ST) and increased the migration speed (24.35%, P < 0.05, n = 4), while DEX impaired ST and migration speed after 24 hrs and 7 days of treatment (-28.69% and -25.37%, respectively; P < 0.05, n = 4). In conclusion, our data suggest that these immunosuppressive drugs each affect MSC morphology and migratory capacity differently, possibly impacting the success of cell therapy. PMID:25756665

  13. Adult human mesenchymal stem cells enhance breast tumorigenesis and promote hormone independence

    PubMed Central

    Rhodes, Lyndsay V.; Muir, Shannon E.; Elliott, Steven; Guillot, Lori M.; Antoon, James W.; Penfornis, Patrice; Tilghman, Syreeta L.; Salvo, Virgilio A.; Fonseca, Juan P.; Lacey, Michelle R.; Beckman, Barbara S.; McLachlan, John A.; Rowan, Brian G.; Pochampally, Radhika

    2016-01-01

    Adult human mesenchymal stem cells (hMSCs) have been shown to home to sites of breast cancer and integrate into the tumor stroma. We demonstrate here the effect of hMSCs on primary breast tumor growth and the progression of these tumors to hormone independence. Co-injection of bone marrow-derived hMSCs enhances primary tumor growth of the estrogen receptor-positive, hormone-dependent breast carcinoma cell line MCF-7 in the presence or absence of estrogen in SCID/beige mice. We also show hormone-independent growth of MCF-7 cells when co-injected with hMSCs. These effects were found in conjunction with increased immunohistochemical staining of the progesterone receptor in the MCF-7/hMSC tumors as compared to MCF-7 control tumors. This increase in PgR expression indicates a link between MCF-7 cells and MSCs through ER-mediated signaling. Taken together, our data reveal the relationship between tumor microenvironment and tumor growth and the progression to hormone independence. This tumor stroma-cell interaction may provide a novel target for the treatment of estrogen receptor-positive, hormone-independent, and endocrine-resistant breast carcinoma. PMID:19597705

  14. Autophagy promotes resistance to photodynamic therapy-induced apoptosis selectively in colorectal cancer stem-like cells

    PubMed Central

    Wei, Ming-Feng; Chen, Min-Wei; Chen, Ke-Cheng; Lou, Pei-Jen; Lin, Susan Yun-Fan; Hung, Shih-Chieh; Hsiao, Michael; Yao, Cheng-Jung; Shieh, Ming-Jium

    2014-01-01

    Recent studies have indicated that cancer stem-like cells (CSCs) exhibit a high resistance to current therapeutic strategies, including photodynamic therapy (PDT), leading to the recurrence and progression of colorectal cancer (CRC). In cancer, autophagy acts as both a tumor suppressor and a tumor promoter. However, the role of autophagy in the resistance of CSCs to PDT has not been reported. In this study, CSCs were isolated from colorectal cancer cells using PROM1/CD133 (prominin 1) expression, which is a surface marker commonly found on stem cells of various tissues. We demonstrated that PpIX-mediated PDT induced the formation of autophagosomes in PROM1/CD133+ cells, accompanied by the upregulation of autophagy-related proteins ATG3, ATG5, ATG7, and ATG12. The inhibition of PDT-induced autophagy by pharmacological inhibitors and silencing of the ATG5 gene substantially triggered apoptosis of PROM1/CD133+ cells and decreased the ability of colonosphere formation in vitro and tumorigenicity in vivo. In conclusion, our results revealed a protective role played by autophagy against PDT in CSCs and indicated that targeting autophagy could be used to elevate the PDT sensitivity of CSCs. These findings would aid in the development of novel therapeutic approaches for CSC treatment. PMID:24905352

  15. Nicotinic acetylcholine receptors induce c-Kit ligand/Stem Cell Factor and promote stemness in an ARRB1/ β-arrestin-1 dependent manner in NSCLC

    PubMed Central

    Perumal, Deepak; Pillai, Smitha; Nguyen, Jonathan; Schaal, Courtney; Coppola, Domenico; Chellappan, Srikumar P.

    2014-01-01

    Lung cancer remains the leading cause of cancer-related deaths worldwide. β-arrestin-1 (ARRB1), a scaffolding protein involved in the desensitization of signals arising from activated G-protein-coupled receptors (GPCRs), has been shown to play a role in invasion and proliferation of cancer cells, including nicotine-induced proliferation of human non–small cell lung cancers (NSCLCs). In this study, we identified genes that are differentially regulated by nicotine in an ARRB1/β-arrestin-1 dependent manner in NSCLC cells by microarray analysis. Among the identified genes, SCF (Stem cell factor) strongly differentiated smokers from non-smokers in the Director's Challenge Set expression data and its high expression correlated with poor prognosis. SCF, a major cytokine is the ligand for the c-Kit proto-oncogene and was found to be over expressed in human lung adenocarcinomas, but not squamous cell carcinomas. Data presented here show that transcription factor E2F1 can induce SCF expression at the transcriptional level and depletion of E2F1 or ARRB1/β-arrestin-1 could not promote self-renewal of SP cells. These studies suggest that nicotine might be promoting NSCLC growth and metastasis by inducing the secretion of SCF, and raise the possibility that targeting signalling cascades that activate E2F1 might be an effective way to combat NSCLC. PMID:25401222

  16. Adenovirus-mediated expression of growth and differentiation factor-5 promotes chondrogenesis of adipose stem cells

    PubMed Central

    FENG, GANG; WAN, YUQING; BALIAN, GARY; LAURENCIN, CATO T.; LI, XUDONG

    2010-01-01

    The repair of articular cartilage injuries is impeded by the avascular and non-innervated nature of cartilage. Transplantation of autologous chondrocytes has a limited ability to augment the repair process due to the highly differentiated state of chondrocytes and the risks of donor-site morbidity. Mesenchymal stem cells can undergo chondrogenesis in the presence of growth factors for cartilage defect repair. Growth and differentiation factor-5 (GDF5) plays an important role in chondrogenesis. In this study, we examined the effects of GDF5 on chondrogenesis of adipose-derived stem cells (ADSCs) and evaluate the chondrogenic potentials of GDF5 genetically engineered ADSCs using an in vitro pellet culture model. Rat ADSCs were grown as pellet cultures and treated with chondrogenic media (CM). Induction of GDF5 by an adenovirus (Ad-GDF5) was compared with exogenous supplementation of GDF5 (100 ng/ml) and transforming growth factor-β (TGF-β1; 10 ng/ml). The ADSCs underwent chondrogenic differentiation in response to GDF5 exposure as demonstrated by production of proteoglycan, and up-regulation of collagen II and aggrecan at the protein and mRNA level. The chondrogenic potential of a one-time infection with Ad-GDF5 was weaker than exogenous GDF5, but equal to that of TGF-β1. Stimulation with growth factors or CM alone induced transient expression of the mRNA for collagen X, indicating a need for optimization of the CM. Our findings indicate that GDF5 is a potent inducer of chondrogenesis in ADSCs, and that ADSCs genetically engineered to express prochondrogenic growth factors, such as GDF5, may be a promising therapeutic cell source for cartilage tissue engineering. PMID:18569021

  17. High-dose, post-transplantation cyclophosphamide to promote graft-host tolerance after allogeneic hematopoietic stem cell transplantation

    PubMed Central

    Luznik, Leo

    2010-01-01

    Graft-versus-host disease, or GVHD, is a major complication of allogeneic hematopoietic stem cell transplantation (alloHSCT) for the treatment of hematologic malignancies. Here, we describe a novel method for preventing GVHD after alloHSCT using high-dose, post-transplantation cyclophosphamide (Cy). Post-transplantation Cy promotes tolerance in alloreactive host and donor T cells, leading to suppression of both graft rejection and GVHD after alloHSCT. High-dose, post-transplantation Cy facilitates partially HLA-mismatched HSCT without severe GVHD and is effective as sole prophylaxis of GVHD after HLA-matched alloHSCT. By reducing the morbidity and mortality of alloHSCT, post-transplantation Cy may expand the applications of this therapy to the treatment of autoimmune diseases and non-malignant hematologic disorders such as sickle cell disease. PMID:20066512

  18. Mesenchymal Stem Cells Ageing: Targeting the "Purinome" to Promote Osteogenic Differentiation and Bone Repair.

    PubMed

    Noronha-Matos, J B; Correia-de-Sá, P

    2016-09-01

    Mesenchymal stem cells (MSCs) are multipotent cells that can differentiate into bone forming cells. Such ability is compromised in elderly individuals resulting in bone disorders such as osteoporosis, also limiting their clinical usage for cell transplantation and bone tissue engineering strategies. In bone marrow niches, adenine and uracil nucleotides are important local regulators of osteogenic differentiation of MSCs. Nucleotides can be released to the extracellular milieu under both physiological and pathological conditions via (1) membrane cell damage, (2) vesicle exocytosis, (3) ATP-binding cassette transporters, and/or (4) facilitated diffusion through maxi-anion channels, hemichannels or ligand-gated receptor pores. Nucleotides and their derivatives act via adenosine P1 (A1 , A2A , A2B , and A3 ) and nucleotide-sensitive P2 purinoceptors comprising ionotropic P2X and G-protein-coupled P2Y receptors. Purinoceptors activation is terminated by membrane-bound ecto-nucleotidases and other ecto-phosphatases, which rapidly hydrolyse extracellular nucleotides to their respective nucleoside 5'-di- and mono-phosphates, nucleosides and free phosphates, or pyrophosphates. Current knowledge suggests that different players of the "purinome" cascade, namely nucleotide release sites, ecto-nucleotidases and purinoceptors, orchestrate to fine-tuning regulate the activity of MSCs in the bone microenvironment. Increasing studies, using osteoprogenitor cell lines, animal models and, more recently, non-modified MSCs from postmenopausal women, raised the possibility to target chief components of the purinergic signaling pathway to regenerate the ability of aged MSCs to differentiate into functional osteoblasts. This review summarizes the main findings of those studies, prompting for novel therapeutic strategies to control ageing disorders where bone destruction exceeds bone formation, like osteoporosis, rheumatoid arthritis, and fracture mal-union. J. Cell. Physiol. 231: 1852

  19. A Flavonoid Compound Promotes Neuronal Differentiation of Embryonic Stem Cells via PPAR-β Modulating Mitochondrial Energy Metabolism

    PubMed Central

    Mei, Yu-qin; Pan, Zong-fu; Chen, Wen-teng; Xu, Min-hua; Zhu, Dan-yan; Yu, Yong-ping; Lou, Yi-jia

    2016-01-01

    Relatively little is known regarding mitochondrial metabolism in neuronal differentiation of embryonic stem (ES) cells. By using a small molecule, present research has investigated the pattern of cellular energy metabolism in neural progenitor cells derived from mouse ES cells. Flavonoid compound 4a faithfully facilitated ES cells to differentiate into neurons morphologically and functionally. The expression and localization of peroxisome proliferator-activated receptors (PPARs) were examined in neural progenitor cells. PPAR-β expression showed robust upregulation compared to solvent control. Treatment with PPAR-β agonist L165041 alone or together with compound 4a significantly promoted neuronal differentiation, while antagonist GSK0660 blocked the neurogenesis-promoting effect of compound 4a. Consistently, knockdown of PPAR-β in ES cells abolished compound 4a-induced neuronal differentiation. Interestingly, we found that mitochondrial fusion protein Mfn2 was also abolished by sh-PPAR-β, resulting in abnormal mitochondrial Ca2+ ([Ca2+]M) transients as well as impaired mitochondrial bioenergetics. In conclusion, we demonstrated that by modulating mitochondrial energy metabolism through Mfn2 and mitochondrial Ca2+, PPAR-β took an important role in neuronal differentiation induced by flavonoid compound 4a. PMID:27315062

  20. A Flavonoid Compound Promotes Neuronal Differentiation of Embryonic Stem Cells via PPAR-β Modulating Mitochondrial Energy Metabolism.

    PubMed

    Mei, Yu-Qin; Pan, Zong-Fu; Chen, Wen-Teng; Xu, Min-Hua; Zhu, Dan-Yan; Yu, Yong-Ping; Lou, Yi-Jia

    2016-01-01

    Relatively little is known regarding mitochondrial metabolism in neuronal differentiation of embryonic stem (ES) cells. By using a small molecule, present research has investigated the pattern of cellular energy metabolism in neural progenitor cells derived from mouse ES cells. Flavonoid compound 4a faithfully facilitated ES cells to differentiate into neurons morphologically and functionally. The expression and localization of peroxisome proliferator-activated receptors (PPARs) were examined in neural progenitor cells. PPAR-β expression showed robust upregulation compared to solvent control. Treatment with PPAR-β agonist L165041 alone or together with compound 4a significantly promoted neuronal differentiation, while antagonist GSK0660 blocked the neurogenesis-promoting effect of compound 4a. Consistently, knockdown of PPAR-β in ES cells abolished compound 4a-induced neuronal differentiation. Interestingly, we found that mitochondrial fusion protein Mfn2 was also abolished by sh-PPAR-β, resulting in abnormal mitochondrial Ca2+ ([Ca2+]M) transients as well as impaired mitochondrial bioenergetics. In conclusion, we demonstrated that by modulating mitochondrial energy metabolism through Mfn2 and mitochondrial Ca2+, PPAR-β took an important role in neuronal differentiation induced by flavonoid compound 4a. PMID:27315062

  1. Nuclear Factor I-C promotes proliferation and differentiation of apical papilla-derived human stem cells in vitro

    SciTech Connect

    Zhang, Jing; Wang, Zhihua; Jiang, Yong; Niu, Zhongying; Fu, Lei; Luo, Zhirong; Cooper, Paul R.; Smith, Anthony J.; He, Wenxi

    2015-03-15

    The transcription factor Nuclear Factor I-C (NFIC) has been implicated in the regulation of tooth root development, where it may be anticipated to impact on the behavior of stem cells from the apical papilla (SCAPs) and root odontoblast activity. We hypothesized that NFIC may provide an important target for promoting dentin/root regeneration. In the present study, the effects of NFIC on the proliferation and differentiation of SCAPs were investigated. Over-expression of NFIC increased cell proliferation, mineralization nodule formation and alkaline phosphatase (ALP) activity in SCAPs. Furthermore, NFIC up-regulated the mRNA levels of odontogenic-related markers, ALP, osteocalcin and collagen type I as well as dentin sialoprotein protein levels. In contrast, knockdown of NFIC by si-RNA inhibited the mineralization capacity of SCAPs and down-regulated the expression of odontogenic-related markers. In conclusion, the results indicated that upregulation of NFIC activity in SCAPs may promote osteo/odontoblastic differentiation of SCAPs. - Highlights: • NFIC promotes the proliferation of SCAPs in vitro. • NFIC promotes osteo/odontogenic differentiation of SCAPs in vitro. • Knockdown of NFIC inhibits odontogenic differentiation in SCAPs.

  2. Autocrine production of TGF-β1 promotes myofibroblastic differentiation of neonatal lung mesenchymal stem cells

    PubMed Central

    Popova, Antonia P.; Bozyk, Paul D.; Goldsmith, Adam M.; Linn, Marisa J.; Lei, Jing; Bentley, J. Kelley

    2010-01-01

    We have isolated mesenchymal stem cells (MSCs) from tracheal aspirates of premature infants with respiratory distress. We examined the capacity of MSCs to differentiate into myofibroblasts, cells that participate in lung development, injury, and repair. Gene expression was measured by array, qPCR, immunoblot, and immunocytochemistry. Unstimulated MSCs expressed mRNAs encoding contractile (e.g., ACTA2, TAGLN), extracellular matrix (COL1A1 and ELN), and actin-binding (DBN1, PXN) proteins, consistent with a myofibroblast phenotype, although there was little translation into immunoreactive protein. Incubation in serum-free medium increased contractile protein (ACTA2, MYH11) gene expression. MSC-conditioned medium showed substantial levels of TGF-β1, and treatment of serum-deprived cells with a type I activin receptor-like kinase inhibitor, SB-431542, attenuated the expression of genes encoding contractile and extracellular matrix proteins. Treatment of MSCs with TGF-β1 further induced the expression of mRNAs encoding contractile (ACTA2, MYH11, TAGLN, DES) and extracellular matrix proteins (FN1, ELN, COL1A1, COL1A2), and increased the protein expression of α-smooth muscle actin, myosin heavy chain, and SM22. In contrast, human bone marrow-derived MSCs failed to undergo TGF-β1-induced myofibroblastic differentiation. Finally, primary cells from tracheal aspirates behaved in an identical manner as later passage cells. We conclude that human neonatal lung MSCs demonstrate an mRNA expression pattern characteristic of myofibroblast progenitor cells. Autocrine production of TGF-β1 further drives myofibroblastic differentiation, suggesting that, in the absence of other signals, fibrosis represents the “default program” for neonatal lung MSC gene expression. These data are consistent with the notion that MSCs play a key role in neonatal lung injury and repair. PMID:20190033

  3. Stem cell biobanks.

    PubMed

    Bardelli, Silvana

    2010-04-01

    Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment. PMID:20560026

  4. P53 functional abnormality in mesenchymal stem cells promotes osteosarcoma development

    PubMed Central

    Velletri, T; Xie, N; Wang, Y; Huang, Y; Yang, Q; Chen, X; Chen, Q; Shou, P; Gan, Y; Cao, G; Melino, G; Shi, Y

    2016-01-01

    It has been shown that p53 has a critical role in the differentiation and functionality of various multipotent progenitor cells. P53 mutations can lead to genome instability and subsequent functional alterations and aberrant transformation of mesenchymal stem cells (MSCs). The significance of p53 in safeguarding our body from developing osteosarcoma (OS) is well recognized. During bone remodeling, p53 has a key role in negatively regulating key factors orchestrating the early stages of osteogenic differentiation of MSCs. Interestingly, changes in the p53 status can compromise bone homeostasis and affect the tumor microenvironment. This review aims to provide a unique opportunity to study the p53 function in MSCs and OS. In the context of loss of function of p53, we provide a model for two sources of OS: MSCs as progenitor cells of osteoblasts and bone tumor microenvironment components. Standing at the bone remodeling point of view, in this review we will first explain the determinant function of p53 in OS development. We will then summarize the role of p53 in monitoring MSC fidelity and in regulating MSC differentiation programs during osteogenesis. Finally, we will discuss the importance of loss of p53 function in tissue microenvironment. We expect that the information provided herein could lead to better understanding and treatment of OS. PMID:26775693

  5. Resveratrol-induced SIRT1 activation promotes neuronal differentiation of human bone marrow mesenchymal stem cells.

    PubMed

    Joe, I-Seul; Jeong, Sin-Gu; Cho, Goang-Won

    2015-01-01

    Resveratrol-3,4',5-trihydroxy-trans-stillbene (resveratrol; RSV), a natural non-flavonoid polyphenol compound, provides protection against stress injury, excessive sunlight, ultraviolet radiation, infections, and invading fungi. There is increasing evidence that resveratrol, a sirtuin1 activator, plays a pivotal role in neuroprotection and neuronal differentiation. In this study, we investigated whether resveratrol induces neuronal differentiation of human bone marrow-mesenchymal stem cells (hBM-MSCs). Quantitative PCR results showed that resveratrol-treated MSCs (RSV-MSCs) had significantly increased expression of the neuroprogenitor markers Nestin, Musashi, CD133, and GFAP. When RSV-MSCs were differentiated with neuronal induction media (RSV-dMSCs), they exhibited a cell body and dendritic morphology similar to neurons. The number and neurite length of these RSV-dMSCs were significantly increased compared to differentiated MSCs (dMSCs). The RSV-dMSCs and dMSCs had significantly increased expression of the neuronal-specific marker genes Nestin, Musashi, CD133, GFAP, NF-M, MAP-2, and KCNH1. The RSV-dMSCs also showed a higher expression of the neuronal marker proteins, Nestin and NF-M, based on immunocytochemical staining and immunoblot analysis. This effect was abolished by the treatment of sirtuin1 inhibitor EX527. Therefore, we have shown that resveratrol treatment, along with the use of neuronal induction media, effectively stimulates neuronal cell differentiation of hBM-MSCs. PMID:25459285

  6. Mutant Kras Promotes Hyperplasia and Alters Differentiation in the Colon Epithelium But Does Not Expand the Presumptive Stem Cell Pool

    PubMed Central

    Feng, Ying; Bommer, Guido T.; Zhao, Jenny; Green, Maranne; Sands, Evan; Zhai, Yali; Brown, Kelly; Burberry, Aaron; Cho, Kathleen R.; Fearon, Eric R.

    2011-01-01

    BACKGROUND & AIMS Adenomatous polyps are precursors to colorectal cancer (CRC), whereas hyperplastic polyps (HPPs) have a small risk of progression to CRC. Mutations in KRAS are found in ~40% of CRCs and large adenomas and a subset of HPPs. We investigated the reasons that HPPs with KRAS mutations lack malignant potential; we compared the effects of Kras/KRAS activation to those of Adenomatous polyposis coli (Apc)/APC inactivation, which promotes adenoma formation. METHODS We activated a KrasG12D mutant allele or inactivated Apc alleles in mouse colon epithelium and analyzed phenotypes and expression of selected genes and proteins. The mouse data were validated using samples of human HPPs and adenomas. Signaling pathways and factors that contribute to Kras/KRAS-induced phenotypes were studied in intestinal epithelial cells. RESULTS Activation of Kras led to hyperplasia and serrated crypt architecture akin to that observed in human HPPs. We also observed loss of Paneth cells and increases in goblet cell numbers. Abnormalities in Kras-mediated differentiation and proliferation required mitogen-activated protein kinase (MAPK) signaling and were linked to activation of the Hes1 transcription factor. Human HPPs also had activation of HES1. In contrast to Apc/APC inactivation, Kras/KRAS activation did not increase expression of crypt stem cell markers in colon epithelium or colony formation in vitro. Kras/KRAS activation was not associated with substantial induction of p16INK4a protein expression in mouse colon epithelium or human HPPs. CONCLUSIONS Although Kras/KRAS mutation promotes serrated and hyperplastic morphological features in colon epithelium, it is not able to initiate adenoma development, perhaps in part because activated Kras/KRAS signaling does not increase the number of presumptive stem cells in affected crypts. PMID:21699772

  7. CD105 promotes chondrogenesis of synovium-derived mesenchymal stem cells through Smad2 signaling.

    PubMed

    Fan, Wenshuai; Li, Jinghuan; Wang, Yiming; Pan, Jianfeng; Li, Shuo; Zhu, Liang; Guo, Changan; Yan, Zuoqin

    2016-05-27

    Mesenchymal stem cells (MSCs) are considered to be suitable for cell-based tissue regeneration. Expressions of different cell surface markers confer distinct differentiation potential to different sub-populations of MSCs. Understanding the effect of cell surface markers on MSC differentiation is essential to their targeted application in different tissues. Although CD105 positive MSCs possess strong chondrogenic capacity, the underlying mechanisms are not clear. In this study, we observed a considerable heterogeneity with respect to CD105 expression among MSCs isolated from synovium. The CD105(+) and CD105(-) synovium-derived MSCs (SMSCs) were sorted to compare their differentiation capacities and relative gene expressions. CD105(+) subpopulation had higher gene expressions of AGG, COL II and Sox9, and showed a stronger affinity for Alcian blue and immunofluorescent staining for aggrecan and collagenase II, as compared to those in CD105(-) cells. However, no significant difference was observed with respect to gene expressions of ALP, Runx2, LPL and PPARγ. CD105(+) SMSCs showed increased levels of Smad2 phosphorylation, while total Smad2 levels were similar between the two groups. There was no difference in activation of Smad1/5. These results were further confirmed by CD105-knockdown in SMSCs. Our findings suggest a stronger chondrogenic potential of CD105(+) SMSCs in comparison to that of CD105(-) SMSCs and that CD105 enhances chondrogenesis of SMSCs by regulating TGF-β/Smad2 signaling pathway, but not Smad1/5. Our study provides a better understanding of CD105 with respect to chondrogenic differentiation. PMID:27107692

  8. Tenascin C Promotes Hematoendothelial Development and T Lymphoid Commitment from Human Pluripotent Stem Cells in Chemically Defined Conditions

    PubMed Central

    Uenishi, Gene; Theisen, Derek; Lee, Jeong-Hee; Kumar, Akhilesh; Raymond, Matt; Vodyanik, Maxim; Swanson, Scott; Stewart, Ron; Thomson, James; Slukvin, Igor

    2014-01-01

    Summary The recent identification of hemogenic endothelium (HE) in human pluripotent stem cell (hPSC) cultures presents opportunities to investigate signaling pathways that are essential for blood development from endothelium and provides an exploratory platform for de novo generation of hematopoietic stem cells (HSCs). However, the use of poorly defined human or animal components limits the utility of the current differentiation systems for studying specific growth factors required for HE induction and manufacturing clinical-grade therapeutic blood cells. Here, we identified chemically defined conditions required to produce HE from hPSCs growing in Essential 8 (E8) medium and showed that Tenascin C (TenC), an extracellular matrix protein associated with HSC niches, strongly promotes HE and definitive hematopoiesis in this system. hPSCs differentiated in chemically defined conditions undergo stages of development similar to those previously described in hPSCs cocultured on OP9 feeders, including the formation of VE-Cadherin+CD73−CD235a/CD43− HE and hematopoietic progenitors with myeloid and T lymphoid potential. PMID:25448067

  9. USP44+ Cancer Stem Cell Subclones Contribute to Breast Cancer Aggressiveness by Promoting Vasculogenic Mimicry.

    PubMed

    Liu, Tieju; Sun, Baocun; Zhao, Xiulan; Li, Yanlei; Zhao, Xueming; Liu, Ying; Yao, Zhi; Gu, Qiang; Dong, Xueyi; Shao, Bing; Lin, Xian; Liu, Fang; An, Jindan

    2015-09-01

    Vasculogenic mimicry (VM), a newly defined pattern of tumor blood supply, describes the functional plasticity of aggressive cancer cells that form vascular networks. In our previous study, breast cancer stem cells (CSC) were shown to potentially participate in VM formation. In this study, breast CSCs presented centrosome amplification (CA) phenotype and ubiquitin-specific protease 44 (USP44) upregulation. USP44 expression contributed to the establishment of bipolar spindles in breast CSCs with supernumerary centrosomes by localizing at pole-associated centrosomes. The bipolar spindle patterns of breast CSCs with CA, including planar-like and apico-basal-like, functioned differently during the VM process of CSCs. Moreover, the ability of transendothelial migration in VM-forming cells was increased. In vivo experiment results showed that CSC xenografts presented linearly patterned programmed cell necrosis, which provided a spatial foundation for VM formation as well as angiogenesis. Breast CSCs further showed increased levels of IL6 and IL8. However, USP44 silencing induced spindle multipolarity, abated VM, reduced transendothelial migration, and consequently decreased IL6 and IL8 levels in breast CSCs. Finally, USP44(+) CSC subclones (ALDH1(+)/USP44(+)/IL6(+)/IL8(+)) were identified in breast cancer specimens through consecutive sections scanning. The subclones were related not only to CA, but also to VM. Statistical analysis suggested that USP44(+) CSC subclones could be used as an independent prognostic biomarker of poor clinical outcomes in patients with breast cancer. Collectively, the identification of USP44(+) CSC subclones may contribute to the prediction of VM formation and aggressive behavior. This study provides novel insights into the therapy for advanced breast cancer. PMID:26232424

  10. Mucosally transplanted mesenchymal stem cells stimulate intestinal healing by promoting angiogenesis

    PubMed Central

    Manieri, Nicholas A.; Mack, Madison R.; Himmelrich, Molly D.; Worthley, Daniel L.; Hanson, Elaine M.; Eckmann, Lars; Wang, Timothy C.; Stappenbeck, Thaddeus S.

    2015-01-01

    Mesenchymal stem cell (MSC) therapy is an emerging field of regenerative medicine; however, it is often unclear how these cells mediate repair. Here, we investigated the use of MSCs in the treatment of intestinal disease and modeled abnormal repair by creating focal wounds in the colonic mucosa of prostaglandin-deficient mice. These wounds developed into ulcers that infiltrated the outer intestinal wall. We determined that penetrating ulcer formation in this model resulted from increased hypoxia and smooth muscle wall necrosis. Prostaglandin I2 (PGI2) stimulated VEGF-dependent angiogenesis to prevent penetrating ulcers. Treatment of mucosally injured WT mice with a VEGFR inhibitor resulted in the development of penetrating ulcers, further demonstrating that VEGF is critical for mucosal repair. We next used this model to address the role of transplanted colonic MSCs (cMSCs) in intestinal repair. Compared with intravenously injected cMSCs, mucosally injected cMSCs more effectively prevented the development of penetrating ulcers, as they were more efficiently recruited to colonic wounds. Importantly, mucosally injected cMSCs stimulated angiogenesis in a VEGF-dependent manner. Together, our results reveal that penetrating ulcer formation results from a reduction of local angiogenesis and targeted injection of MSCs can optimize transplantation therapy. Moreover, local MSC injection has potential for treating diseases with features of abnormal angiogenesis and repair. PMID:26280574

  11. Downregulation of COMMD1 by miR-205 promotes a positive feedback loop for amplifying inflammatory- and stemness-associated properties of cancer cells

    PubMed Central

    Yeh, D-W; Chen, Y-S; Lai, C-Y; Liu, Y-L; Lu, C-H; Lo, J-F; Chen, L; Hsu, L-C; Luo, Y; Xiang, R; Chuang, T-H

    2016-01-01

    Sustained activation of nuclear factor-κB (NF-κB) in cancer cells has been shown to promote inflammation, expansion of cancer stem cell (CSC) population, and tumor development. In contrast, recent studies reveal that CSCs exhibit increased inflammation due to constitutive NF-κB activation; however, the underlying molecular mechanism remains unclear. In the present study, the analysis of microarray data revealed upregulation of NF-κB-regulated pro-inflammatory genes and downregulation of copper metabolism MURR1 domain-containing 1 (COMMD1) during the enrichment for stemness in SAS head and neck squamous-cell carcinoma (HNSCC) cells. The 3′-UTR of COMMD1 mRNA contains microRNA (miR)-205 target site. Parallel studies with HNSCC and NSCLC cells indicated that miR-205 is upregulated upon NF-κB activation and suppresses COMMD1 expression in stemness-enriched cancer cells. COMMD1 negatively regulates the inflammatory responses induced by TLR agonists, IL-1β, and TNF-α by targeting RelA for degradation. The shRNA-mediated downregulation of COMMD1 in cancer cells enhanced inflammatory response, generating favorable conditions for macrophage recruitment. In addition, genes associated with stemness were also upregulated in these cells, which exhibited increased potential for anchorage-independent growth. Furthermore, COMMD1 downregulation promoted in vivo tumorigenesis and tumor growth, and tumors derived from COMMD1-knockdown cells displayed elevated level of NF-κB activation, increased expression of inflammatory- and stemness-associated genes, and contain expanded population of tumor-associated leukocytes and stemness-enriched cancer cells. These results suggest that COMMD1 downregulation by miR-205 promotes tumor development by modulating a positive feedback loop that amplifies inflammatory- and stemness-associated properties of cancer cells. PMID:26586569

  12. Downregulation of COMMD1 by miR-205 promotes a positive feedback loop for amplifying inflammatory- and stemness-associated properties of cancer cells.

    PubMed

    Yeh, D-W; Chen, Y-S; Lai, C-Y; Liu, Y-L; Lu, C-H; Lo, J-F; Chen, L; Hsu, L-C; Luo, Y; Xiang, R; Chuang, T-H

    2016-05-01

    Sustained activation of nuclear factor-κB (NF-κB) in cancer cells has been shown to promote inflammation, expansion of cancer stem cell (CSC) population, and tumor development. In contrast, recent studies reveal that CSCs exhibit increased inflammation due to constitutive NF-κB activation; however, the underlying molecular mechanism remains unclear. In the present study, the analysis of microarray data revealed upregulation of NF-κB-regulated pro-inflammatory genes and downregulation of copper metabolism MURR1 domain-containing 1 (COMMD1) during the enrichment for stemness in SAS head and neck squamous-cell carcinoma (HNSCC) cells. The 3'-UTR of COMMD1 mRNA contains microRNA (miR)-205 target site. Parallel studies with HNSCC and NSCLC cells indicated that miR-205 is upregulated upon NF-κB activation and suppresses COMMD1 expression in stemness-enriched cancer cells. COMMD1 negatively regulates the inflammatory responses induced by TLR agonists, IL-1β, and TNF-α by targeting RelA for degradation. The shRNA-mediated downregulation of COMMD1 in cancer cells enhanced inflammatory response, generating favorable conditions for macrophage recruitment. In addition, genes associated with stemness were also upregulated in these cells, which exhibited increased potential for anchorage-independent growth. Furthermore, COMMD1 downregulation promoted in vivo tumorigenesis and tumor growth, and tumors derived from COMMD1-knockdown cells displayed elevated level of NF-κB activation, increased expression of inflammatory- and stemness-associated genes, and contain expanded population of tumor-associated leukocytes and stemness-enriched cancer cells. These results suggest that COMMD1 downregulation by miR-205 promotes tumor development by modulating a positive feedback loop that amplifies inflammatory- and stemness-associated properties of cancer cells. PMID:26586569

  13. Human umbilical cord derived mesenchymal stem cells promote interleukin-17 production from human peripheral blood mononuclear cells of healthy donors and systemic lupus erythematosus patients.

    PubMed

    Ren, S; Hu, J; Chen, Y; Yuan, T; Hu, H; Li, S

    2016-03-01

    Inflammation instigated by interleukin (IL)-17-producing cells is central to the development and pathogenesis of several human autoimmune diseases and animal models of autoimmunity. The expansion of IL-17-producing cells from healthy donors is reportedly promoted by mesenchymal stem cells derived from fetal bone marrow. In the present study, human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) were examined for their effects on lymphocytes from healthy donors and from patients with systemic lupus erythematosus (SLE). Significantly higher levels of IL-17 were produced when CD4(+) T cells from healthy donors were co-cultured with hUC-MSCs than those that were cultured alone. Blocking experiments identified that this effect might be mediated partially through prostaglandin E2 (PGE2 ) and IL-1β, without IL-23 involvement. We then co-cultured hUC-MSCs with human CD4(+) T cells from systemic lupus erythematosus patients. Ex-vivo inductions of IL-17 by hUC-MSCs in stimulated lymphocytes were significantly higher in SLE patients than in healthy donors. This effect was not observed for IL-23. Taken together, our results represent that hUC-MSCs can promote the IL-17 production from CD4(+) T cells in both healthy donor and SLE patients. PGE2 and IL-1β might also be partially involved in the promotive effect of hUC-MSCs. PMID:26507122

  14. The Interaction between Cancer Stem Cell Marker CD133 and Src Protein Promotes Focal Adhesion Kinase (FAK) Phosphorylation and Cell Migration.

    PubMed

    Liu, Chanjuan; Li, Yinan; Xing, Yang; Cao, Benjin; Yang, Fan; Yang, Tianxiao; Ai, Zhilong; Wei, Yuanyan; Jiang, Jianhai

    2016-07-22

    CD133, a widely known cancer stem cell marker, has been proved to promote tumor metastasis. However, the mechanism by which CD133 regulates metastasis remains largely unknown. Here, we report that CD133 knockdown inhibits cancer cell migration, and CD133 overexpression promotes cell migration. CD133 expression is beneficial to activate the Src-focal adhesion kinase (FAK) signaling pathway. Further studies show that CD133 could interact with Src, and the region between amino acids 845 and 857 in the CD133 C-terminal domain is indispensable for its interaction with Src. The interaction activates Src to phosphorylate its substrate FAK and to promote cell migration. Likewise, a Src binding-deficient CD133 mutant loses the abilities to increase Src and FAK phosphorylation and to promote cell migration. Inhibition of Src activity by PP2, a known Src activity inhibitor, could block the activation of FAK phosphorylation and cell migration induced by CD133. In summary, our data suggest that activation of FAK by the interaction between CD133 and Src promotes cell migration, providing clues to understand the migratory mechanism of CD133(+) tumor cells. PMID:27226554

  15. Interleukin-22 Promotes Proliferation of Liver Stem/Progenitor Cells in Mice and Patients with Chronic HBV Infection

    PubMed Central

    Feng, Dechun; Kong, Xiaoni; Weng, Honglei; Park, Ogyi; Wang, Hua; Dooley, Steven; Gershwin, M. Eric; Gao, Bin

    2012-01-01

    Background & Aims Proliferation of liver stem/progenitor cells (LPCs), which can differentiate into hepatocytes or biliary epithelial cells, is often observed in chronically inflamed regions of liver in patients. We investigated how inflammation might promote proliferation of LPCs. Methods We examined the role of interleukin (IL)-22, a survival factor for hepatocytes, on proliferation of LPCs in patients with chronic hepatitis B virus (HBV) infection and in mice. Proliferation of LPCs in mice was induced by feeding a diet that contained 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). Results Hepatic expression of IL-22 was increased in patients with HBV and correlated with the grade of inflammation and proliferation of LPCs. Mice on the DDC diet that overexpressed an IL-22 transgene specifically in liver (IL-22TG), or that were infected with an IL-22–expressing adenovirus, had increased proliferation of LPCs. Signal transducer and activator of transcription (STAT) 3, a component of the IL-22 signaling pathway, was activated in LPCs isolated from DDC-fed IL-22TG mice. Deletion of STAT3 from livers of IL-22TG mice reduced proliferation of LPCs. Moreover, the receptors IL-22R1 and IL-10R2 were detected on EpCAM+CD45– LPCs isolated from DDC-fed wild-type mice. Culture of these cells with IL-22 activated STAT3 and led to cell proliferation, but IL-22 had no effect on proliferation of STAT3-deficient EpCAM+CD45– LPCs. IL-22 also activated STAT3 and promoted proliferation of cultured BMOL cells (a mouse LPC line). Conclusion In livers of mice and patients with chronic HBV infection, inflammatory cells produce IL-22, which promotes proliferation of LPCs via STAT3. These findings link inflammation with proliferation of LPCs in patients with HBV infection. PMID:22484119

  16. Differentiated adipose-derived stem cells promote the recovery of nociceptor function in rats.

    PubMed

    Nishibayashi, Akimitsu; Tomita, Koichi; Kiya, Koichiro; Yano, Kenji; Hosokawa, Ko

    2016-10-19

    The loss of nociceptive function in the skin because of trauma or surgery can impair the quality of life. The recovery of nociceptor function is mediated by two different axonal responses: nerve growth factor (NGF)-dependent collateral sprouting of undamaged nerves and NGF-independent regeneration of damaged nerves. We reported previously that adipose-derived stem cells (ASCs) can transdifferentiate into Schwann cell (SC)-like cells (dASCs) and that transplantation of dASCs increases axonal density in skin flaps. In the present study, we used an animal model that allowed for the individual assessment of collateral sprouting and regeneration. In-vitro differentiation of ASCs to dASCs significantly increased the production of NGF and brain-derived neurotrophic factor (BDNF) to levels comparable with SCs. In-vivo experiments showed that dASC and SC transplantation significantly increased the area of the mechano-nociceptive field in both collateral sprouting and regeneration models, whereas ASC transplantation exerted no significant effect. Antibody blocking experiment showed that these effects of dASC transplantation in the regeneration model were partly mediated by BDNF. Interestingly, the final areas of nociceptive fields between the two experimental models did not differ significantly for any treatment condition. These results indicate that dASC transplantation differentially facilitates collateral sprouting and axonal regeneration by delivering NGF and other neurotrophic factors (e.g. BDNF), respectively. Although there is a limit to nociceptive field enlargement irrespective of axonal response, dASC transplantation could present a new approach for improving nociceptive function in denervated skin. PMID:27513202

  17. Adipose-derived mesenchymal stem cell transplantation promotes adult neurogenesis in the brains of Alzheimer's disease mice

    PubMed Central

    Yan, Yufang; Ma, Tuo; Gong, Kai; Ao, Qiang; Zhang, Xiufang; Gong, Yandao

    2014-01-01

    In the present study, we transplanted adipose-derived mesenchymal stem cells into the hippocampi of APP/PS1 transgenic Alzheimer's disease model mice. Immunofluorescence staining revealed that the number of newly generated (BrdU+) cells in the subgranular zone of the dentate gyrus in the hippocampus was significantly higher in Alzheimer's disease mice after adipose-derived mesenchymal stem cell transplantation, and there was also a significant increase in the number of BrdU+/DCX+ neuroblasts in these animals. Adipose-derived mesenchymal stem cell transplantation enhanced neurogenic activity in the subventricular zone as well. Furthermore, adipose-derived mesenchymal stem cell transplantation reduced oxidative stress and alleviated cognitive impairment in the mice. Based on these findings, we propose that adipose-derived mesenchymal stem cell transplantation enhances endogenous neurogenesis in both the subgranular and subventricular zones in APP/PS1 transgenic Alzheimer's disease mice, thereby facilitating functional recovery. PMID:25206892

  18. Fucoidan Promotes Early Step of Cardiac Differentiation from Human Embryonic Stem Cells and Long-Term Maintenance of Beating Areas

    PubMed Central

    Hamidi, Sofiane; Letourneur, Didier; Aid-Launais, Rachida; Di Stefano, Antonio; Vainchenker, William; Norol, Françoise

    2014-01-01

    Somatic stem cells require specific niches and three-dimensional scaffolds provide ways to mimic this microenvironment. Here, we studied a scaffold based on Fucoidan, a sulfated polysaccharide known to influence morphogen gradients during embryonic development, to support human embryonic stem cells (hESCs) differentiation toward the cardiac lineage. A macroporous (pore 200 μm) Fucoidan scaffold was selected to support hESCs attachment and proliferation. Using a protocol based on the cardiogenic morphogen bone morphogenic protein 2 (BMP2) and transforming growth factor (TGFβ) followed by tumor necrosis factor (TNFα), an effector of cardiopoietic priming, we examined the cardiac differentiation in the scaffold compared to culture dishes and embryoid bodies (EBs). At day 8, Fucoidan scaffolds supported a significantly higher expression of the 3 genes encoding for transcription factors marking the early step of embryonic cardiac differentiation NKX2.5 (p<0.05), MEF2C (p<0.01), and GATA4 (p<0.01), confirmed by flow cytometry analysis for MEF2C and NKX2.5. The ability of Fucoidan scaffolds to locally concentrate and slowly release TGFβ and TNFα was confirmed by Luminex technology. We also found that Fucoidan scaffolds supported the late stage of embryonic cardiac differentiation marked by a significantly higher atrial natriuretic factor (ANF) expression (p<0.001), although only rare beating areas were observed. We postulated that absence of mechanical stress in the soft hydrogel impaired sarcomere formation, as confirmed by molecular analysis of the cardiac muscle myosin MYH6 and immunohistological staining of sarcomeric α-actinin. Nevertheless, Fucoidan scaffolds contributed to the development of thin filaments connecting beating areas through promotion of smooth muscle cells, thus enabling maintenance of beating areas for up to 6 months. In conclusion, Fucoidan scaffolds appear as a very promising biomaterial to control cardiac differentiation from hESCs that

  19. Mesenchymal Stem Cell Transplantation Promotes Neurogenesis and Ameliorates Autism Related Behaviors in BTBR Mice.

    PubMed

    Segal-Gavish, Hadar; Karvat, Golan; Barak, Noy; Barzilay, Ran; Ganz, Javier; Edry, Liat; Aharony, Israel; Offen, Daniel; Kimchi, Tali

    2016-01-01

    Autism spectrum disorders (ASD) are characterized by social communication deficits, cognitive rigidity, and repetitive stereotyped behaviors. Mesenchymal stem cells (MSC) have a paracrine regenerative effect, and were speculated to be a potential therapy for ASD. The BTBR inbred mouse strain is a commonly used model of ASD as it demonstrates robust behavioral deficits consistent with the diagnostic criteria for ASD. BTBR mice also exhibit decreased brain-derived neurotrophic factor (BDNF) signaling and reduced hippocampal neurogenesis. In the current study, we evaluated the behavioral and molecular effects of intracerebroventricular MSC transplantation in BTBR mice. Transplantation of MSC resulted in a reduction of stereotypical behaviors, a decrease in cognitive rigidity and an improvement in social behavior. Tissue analysis revealed elevated BDNF protein levels in the hippocampus accompanied by increased hippocampal neurogenesis in the MSC-transplanted mice compared with sham treated mice. This might indicate a possible mechanism underpinning the behavioral improvement. Our study suggests a novel therapeutic approach which may be translatable to ASD patients in the future. PMID:26257137

  20. MicroRNA-127 Promotes Mesendoderm Differentiation of Mouse Embryonic Stem Cells by Targeting Left-Right Determination Factor 2.

    PubMed

    Ma, Haixia; Lin, Yu; Zhao, Zhen-Ao; Lu, Xukun; Yu, Yang; Zhang, Xiaoxin; Wang, Qiang; Li, Lei

    2016-06-01

    Specification of the three germ layers is a fundamental process and is essential for the establishment of organ rudiments. Multiple genetic and epigenetic factors regulate this dynamic process; however, the function of specific microRNAs in germ layer differentiation remains unknown. In this study, we established that microRNA-127 (miR-127) is related to germ layer specification via microRNA array analysis of isolated three germ layers of E7.5 mouse embryos and was verified through differentiation of mouse embryonic stem cells. miR-127 is highly expressed in endoderm and primitive streak. Overexpression of miR-127 increases and inhibition of miR-127 decreases the expression of mesendoderm markers. We further show that miR-127 promotes mesendoderm differentiation through the nodal pathway, a determinative signaling pathway in early embryogenesis. Using luciferase reporter assay, left-right determination factor 2 (Lefty2), an antagonist of nodal, is identified to be a novel target of miR-127. Furthermore, the role of miR-127 in mesendoderm differentiation is attenuated by Lefty2 overexpression. Altogether, our results indicate that miR-127 accelerates mesendoderm differentiation of mouse embryonic stem cells through nodal signaling by targeting Lefty2. PMID:27072135

  1. Differentiation of P19 embryonal carcinoma stem cells into insulin-producing cells promoted by pancreas-conditioned medium.

    PubMed

    Mansouri, Akram; Esmaeili, Fariba; Nejatpour, Azadeh; Houshmand, Fariba; Shabani, Leila; Ebrahimie, Esmaeil

    2016-07-01

    The ability of embryonal carcinoma )EC (stem cells to generate insulin-producing cells (IPCs) is still unknown. We examined the trophic effects of pancreas-conditioned medium (PCM) on in vitro production of IPCs. Initially, P19 EC cells were characterized by the expression of stem cell markers, Oct3/4, Sox-2 and Nanog. To direct differentiation, P19-derived embryoid bodies (EBs) were induced by selection of nestin-positive cells and treatment with different concentrations of PCM. Morphological studies documented the presence of islet-like cell IPCs clusters. The differentiated cells were immunoreactive for β cell-specific proteins, including insulin, proinsulin, C-peptide and insulin receptor-β. The expression of genes related to pancreatic β cell development and function (PDX-1, INS1, INS2, EP300 and CREB1) was confirmed by qPCR. During differentiation, the expression of EP300 and CREB1 increased by 2.5 and 3.1 times, respectively. In contrast, a sharp decrease in the expression of Oct3/4, Sox-2 and Nanog by 4, 1.5 and 1.5 times, respectively, was observed. The differentiated cells were functionally active, synthesizing and secreting insulin in a glucose-regulated manner. Network prediction highlighted crosstalk between PDX-1 transcription factor and INS2 ligand in IPC generation and revealed positive regulatory effects of EP300, CREB1, PPARA, EGR, KIT, GLP1R, and PKT2 on activation of PDX-1 and INS2. This is the first report of the induction of IPC differentiation from EC cells by using neonate mouse PCM. Since P19 EC cells are widely available, easily cultured without feeders and do not require special growth conditions, they would provide a valuable tool for studying pancreatic β cell differentiation and development. Copyright © 2016 John Wiley & Sons, Ltd. PMID:25044225

  2. Suppression of Homeobox Transcription Factor VentX Promotes Expansion of Human Hematopoietic Stem/Multipotent Progenitor Cells

    PubMed Central

    Gao, Hong; Wu, Xiaoming; Sun, Yan; Zhou, Shuanhu; Silberstein, Leslie E.; Zhu, Zhenglun

    2012-01-01

    Mechanisms that regulate proliferation and expansion of human hematopoietic stem/multipotent progenitor cells (HSC/MPPs) are targets of intensive investigations. Several cell intrinsic factors and signaling pathways have been implicated in the proliferation and differentiation of human HSC/MPPs. Nevertheless, expansion of human HSC/MPPs for clinical application remains a critical challenge. VentX is a human homeobox transcription factor that was recently identified as an anti-proliferation and pro-differentiation factor in human hematopoietic cells. Here, we report that VentX expression is up-regulated during ontogenesis of human hematopoietic cells. Strikingly, suppression of VentX expression led to significant expansion of HSC/MPPs ex vivo and a 20-fold increase in engraftment potential in the NOD/SCID/IL2Rγ2null mouse model. VentX suppression helped preserve the HSC/MPP pools and promote clonogenicity of hematopoietic progenitor cells. Mechanistically, we show that VentX regulates critical cell cycle regulators and Wnt downstream genes previously implicated in HSC/MPP proliferation and expansion. PMID:22791709

  3. The RUNX1 +24 enhancer and P1 promoter identify a unique subpopulation of hematopoietic progenitor cells derived from human pluripotent stem cells.

    PubMed

    Ferrell, Patrick I; Xi, Jiafei; Ma, Chao; Adlakha, Mitali; Kaufman, Dan S

    2015-04-01

    Derivation of hematopoietic stem cells (HSCs) from human pluripotent stem cells remains a key goal for the fields of developmental biology and regenerative medicine. Here, we use a novel genetic reporter system to prospectively identify and isolate early hematopoietic cells derived from human embryonic stem cells (hESCs) and human induced pluripotent cells (iPSCs). Cloning the human RUNX1c P1 promoter and +24 enhancer to drive expression of tdTomato (tdTom) in hESCs and iPSCs, we demonstrate that tdTom expression faithfully enriches for RUNX1c-expressing hematopoietic progenitor cells. Time-lapse microscopy demonstrated the tdTom(+) hematopoietic cells to emerge from adherent cells. Furthermore, inhibition of primitive hematopoiesis by blocking Activin/Nodal signaling promoted the expansion and/or survival of the tdTom(+) population. Notably, RUNX1c/tdTom(+) cells represent only a limited subpopulation of the CD34(+) CD45(+) and CD34(+) CD43(+) cells with a unique genetic signature. Using gene array analysis, we find significantly lower expression of Let-7 and mir181a microRNAs in the RUNX1c/tdTom(+) cell population. These phenotypic and genetic analyses comparing the RUNX1c/tdTom(+) population to CD34(+) CD45(+) umbilical cord blood and fetal liver demonstrate several key differences that likely impact the development of HSCs capable of long-term multilineage engraftment from hESCs and iPSCs. PMID:25546363

  4. Proton-sensing GPCR-YAP Signalling Promotes Cancer-associated Fibroblast Activation of Mesenchymal Stem Cells

    PubMed Central

    Zhu, Hongyi; Guo, Shangchun; Zhang, Yuelei; Yin, Junhui; Yin, Wenjing; Tao, Shicong; Wang, Yang; Zhang, Changqing

    2016-01-01

    The pHs of extracellular fluids (ECFs) in normal tissues are commonly maintained at 7.35 to 7.45. The acidification of the ECF is one of the major characteristics of tumour microenvironment. In this study, we report that decreased extracellular pH promotes the transformation of mesenchymal stem cells (MSCs) into cancer-associated fibroblasts (CAFs), termed CAF activation. Furthermore, we demonstrate that GPR68, a proton-sensing G-protein-coupled receptor (GPCR), is required for the pH-dependent regulation of the differentiation of MSCs into CAFs. We then identify Yes-associated protein 1 (YAP) as a downstream effector of GPR68 for CAF activation. Finally, we show that knockdown of GPR68 in MSCs can prevent the CAF activation under cancer microenvironment. Systemic transplantation of GPR68-silenced MSCs suppresses in-situ tumour growth and prolong life span after cancer graft. PMID:27019624

  5. Proton-sensing GPCR-YAP Signalling Promotes Cancer-associated Fibroblast Activation of Mesenchymal Stem Cells.

    PubMed

    Zhu, Hongyi; Guo, Shangchun; Zhang, Yuelei; Yin, Junhui; Yin, Wenjing; Tao, Shicong; Wang, Yang; Zhang, Changqing

    2016-01-01

    The pHs of extracellular fluids (ECFs) in normal tissues are commonly maintained at 7.35 to 7.45. The acidification of the ECF is one of the major characteristics of tumour microenvironment. In this study, we report that decreased extracellular pH promotes the transformation of mesenchymal stem cells (MSCs) into cancer-associated fibroblasts (CAFs), termed CAF activation. Furthermore, we demonstrate that GPR68, a proton-sensing G-protein-coupled receptor (GPCR), is required for the pH-dependent regulation of the differentiation of MSCs into CAFs. We then identify Yes-associated protein 1 (YAP) as a downstream effector of GPR68 for CAF activation. Finally, we show that knockdown of GPR68 in MSCs can prevent the CAF activation under cancer microenvironment. Systemic transplantation of GPR68-silenced MSCs suppresses in-situ tumour growth and prolong life span after cancer graft. PMID:27019624

  6. miR-942 promotes cancer stem cell-like traits in esophageal squamous cell carcinoma through activation of Wnt/β-catenin signalling pathway

    PubMed Central

    Liu, Zhimin; Zhang, Jianhua; Wang, Zhenyu; Li, Ruilei; Zhang, Zhiwei; Li, Zhen; Dong, Suwei; Wang, Ying; Xue, Yuanbo; Yang, Jinyan; Tan, Qinghua; Wang, Ziping; Song, Xin

    2015-01-01

    The Wnt/β-catenin signalling pathway is known to play a vital role in the maintenance of cancer stem cells (CSCs), which are reported to be the origine of malignant cancers, and result in poor prognosis of multiple kinds of cancer. Therefore, it is of great importance to illuminate the mechanism by which the Wnt/β-catenin pathway regulates the cancer stem cell-like traits in cancers. Here, we report that miR-942 is significantly upregulated in esophageal squamous cell carcinoma (ESCC), and miR-942 levels are associated with poor prognosis in ESCC patients. Overexpression of miR-942 promotes, whereas inhibition of miR-942 decreases, the tumor sphere formation, the CD90+ subpopulation cells and the expression of pluripotency associated markers. Moreover, in vivo assay shows that miR-942 overexpressing cells form larger tumors and display higher tumourigenesis. Furthermore, we demonstrate that miR-942 upregulates the Wnt/β-catenin signaling activity via directly targeting sFRP4, GSK3β and TLE1, which are multiple level negative regulators of the Wnt/β-catenin signaling cascade. In addition, our results indicate that c-myc directly binds to the miR-942 promoter and promotes its expression. Taken together, our findings establish an oncogenic role of miR-942 in ESCC and indicate that miR-942 might be an effective therapeutic target for ESCC. PMID:25844602

  7. miR-942 promotes cancer stem cell-like traits in esophageal squamous cell carcinoma through activation of Wnt/β-catenin signalling pathway.

    PubMed

    Ge, Chunlei; Wu, Shikai; Wang, Weiwei; Liu, Zhimin; Zhang, Jianhua; Wang, Zhenyu; Li, Ruilei; Zhang, Zhiwei; Li, Zhen; Dong, Suwei; Wang, Ying; Xue, Yuanbo; Yang, Jinyan; Tan, Qinghua; Wang, Ziping; Song, Xin

    2015-05-10

    The Wnt/β-catenin signalling pathway is known to play a vital role in the maintenance of cancer stem cells (CSCs), which are reported to be the origin of malignant cancers, and result in poor prognosis of multiple kinds of cancer. Therefore, it is of great importance to illuminate the mechanism by which the Wnt/β-catenin pathway regulates the cancer stem cell-like traits in cancers. Here, we report that miR-942 is significantly upregulated in esophageal squamous cell carcinoma (ESCC), and miR-942 levels are associated with poor prognosis in ESCC patients. Overexpression of miR-942 promotes, whereas inhibition of miR-942 decreases, the tumor sphere formation, the CD90+ subpopulation cells and the expression of pluripotency associated markers. Moreover, in vivo assay shows that miR-942 overexpressing cells form larger tumors and display higher tumourigenesis. Furthermore, we demonstrate that miR-942 upregulates the Wnt/β-catenin signaling activity via directly targeting sFRP4, GSK3β and TLE1, which are multiple level negative regulators of the Wnt/β-catenin signaling cascade. In addition, our results indicate that c-myc directly binds to the miR-942 promoter and promotes its expression. Taken together, our findings establish an oncogenic role of miR-942 in ESCC and indicate that miR-942 might be an effective therapeutic target for ESCC. PMID:25844602

  8. Transforming growth factor-beta1 promotes the migration and invasion of sphere-forming stem-like cell subpopulations in esophageal cancer

    SciTech Connect

    Yue, Dongli; Zhang, Zhen; Li, Jieyao; Chen, Xinfeng; Ping, Yu; Liu, Shasha; Shi, Xiaojuan; Li, Lifeng; Wang, Liping; Huang, Lan; Zhang, Bin; and others

    2015-08-01

    Esophageal cancer is one of the most lethal solid malignancies. Mounting evidence demonstrates that cancer stem cells (CSCs) are able to cause tumor initiation, metastasis and responsible for chemotherapy and radiotherapy failures. As CSCs are thought to be the main reason of therapeutic failure, these cells must be effectively targeted to elicit long-lasting therapeutic responses. We aimed to enrich and identify the esophageal cancer cell subpopulation with stem-like properties and help to develop new target therapy strategies for CSCs. Here, we found esophageal cancer cells KYSE70 and TE1 could form spheres in ultra low attachment surface culture and be serially passaged. Sphere-forming cells could redifferentiate and acquire morphology comparable to parental cells, when return to adherent culture. The sphere-forming cells possessed the key criteria that define CSCs: persistent self-renewal, overexpression of stemness genes (SOX2, ALDH1A1 and KLF4), reduced expression of differentiation marker CK4, chemoresistance, strong invasion and enhanced tumorigenic potential. SB525334, transforming growth factor-beta 1(TGF-β1) inhibitor, significantly inhibited migration and invasion of sphere-forming stem-like cells and had no effect on sphere-forming ability. In conclusion, esophageal cancer sphere-forming cells from KYSE70 and TE1 cultured in ultra low attachment surface possess cancer stem cell properties, providing a model for CSCs targeted therapy. TGF-β1 promotes the migration and invasion of sphere-forming stem-like cells, which may guide future studies on therapeutic strategies targeting these cells. - Highlights: • Esophageal cancer sphere-forming cells possess cancer stem cell properties. • Sphere-forming cells enhance TGF-β1 pathway activity. • TGF-β 1 inhibitor suppresses the migration and invasion of sphere-forming cells.

  9. Bone marrow-derived mesenchymal stem cells in three-dimensional culture promote neuronal regeneration by neurotrophic protection and immunomodulation.

    PubMed

    Han, Sufang; Wang, Bin; Li, Xing; Xiao, Zhifeng; Han, Jin; Zhao, Yannan; Fang, Yongxiang; Yin, Yanyun; Chen, Bing; Dai, Jianwu

    2016-07-01

    Accumulating evidence has revealed three-dimensional (3D) culture could better mimic the stem cell niche in vivo in comparison with conventional two-dimensional (2D) culture. In this study, we found that bone marrow derived mesenchymal stem cells (BMSCs) cultured in 3D collagen scaffold (3D BMSCs) exhibited distinctive features including significantly enhancing neurotrophic factor secretions and reducing macrophage activations challenged by lipopolysaccharide (LPS) in vitro. To further evaluate 3D BMSCs' potential benefits to the regeneration of spinal cord injury (SCI), the 3D and 2D BMSCs were respectively implanted in rat hemisected SCI. Compared with 2D cohort, 3D BMSCs transplantation significantly reduced the expressions of inflammatory cytokines such as TNF-α, IL-1β, and IL-6 at 5 days after transplantation, markedly enhanced axonal regeneration, and promoted motor functional recovery during 8 weeks of observation. When Nocodazole was used to depolymerize the cytoskeleton of 3D BMSCs, the changed expressions of neurotrophic factors and inflammatory cytokines were blunted, at least partially. Thus synergistic effects of neuronal protection and immunomodulation of 3D BMSCs may lead to a better functional recovery of SCI and the underlying mechanism may involve the alteration of their cellular morphology because of 3D culture. This study contributes to a better understanding of the cellular characteristics of 3D BMSCs and provides a novel strategy to promote the repair of the injured spinal cord. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1759-1769, 2016. PMID:26990583

  10. Mesenchymal stem cells promote tumor angiogenesis via the action of transforming growth factor β1

    PubMed Central

    LI, GUO-CAI; ZHANG, HONG-WEI; ZHAO, QING-CHUN; SUN, LI; YANG, JIAN-JUN; HONG, LIU; FENG, FAN; CAI, LEI

    2016-01-01

    Mesenchymal stem cells (MSCs) may influence the growth and metastasis of various human malignancies, including hepatocellular carcinoma (HCC). Therefore, the underlying mechanisms via which MSCs are able to affect malignancies require investigation. In the present study, the potential role of MSC in the angiogenesis of HCC was investigated. A total of 17 nude mouse models exhibiting human HCC were used to evaluate the effects of MSC on angiogenesis. A total of 8 mice were injected with human MSCs via the tail vein, and the remaining 9 mice were injected with phosphate-buffered saline as a control. A total of 35 days subsequent to the injection of MSCs, the microvessel density (MVD) of tumors was evaluated by immunostaining, using cluster of differentiation 31 antibody. The mRNA levels of transforming growth factor (TGF)β1, Smad2 and Smad7 were detected using reverse transcription-quantitative polymerase chain reaction. Protein expression levels of TGFβ1 and vascular endothelial growth factor (VEGF) in tumor tissues were analyzed using ELISA. Compared with controls, MVD in MSC-treated mice was significantly increased (28.00±9.19 vs. 18.11±3.30; P=0.006). The levels of TGFβ1 mRNA in the MSC-treated group were 2.15-fold higher compared with the control group (1.27±0.61 vs. 0.59±0.39; P=0.033), and MVD was higher in the group exhibiting increased TGFβ1 mRNA levels compared with the control group (26.50±9.11 vs. 19.44±6.14; P=0.038). In addition, a close correlation between the expression levels of TGFβ1 and VEGF was identified. The results of the present study suggested that MSCs may be capable of enhancing the angiogenesis of HCC, which may be partly due to the involvement of TGFβ1. PMID:26893697

  11. Co-culture of outgrowth endothelial cells with human mesenchymal stem cells in silk fibroin hydrogels promotes angiogenesis.

    PubMed

    Sun, Wei; Motta, Antonella; Shi, Yang; Seekamp, Andreas; Schmidt, Harald; Gorb, Stanislav N; Migliaresi, Claudio; Fuchs, Sabine

    2016-01-01

    Sufficient vascularization of the implant construct is required for tissue regeneration to ensure the supply of oxygen and nutrients. In our previous work, we established sonication-induced silk fibroin hydrogel to load neural stem cells for brain tissue engineering applications. In this study, we explored the application of silk fibroin as an injectable hydrogel for vascularization of soft tissues. We investigated the ability of outgrowth endothelial cells (OECs) in mono-culture or in co-culture with human bone marrow-derived mesenchymal stem cells (BM-MSCs) to form capillary networks in silk fibroin hydrogels. Furthermore, the silk fibroin hydrogel was modified with IKVAV peptide revealing a sequence derived from the extracellular matrix component laminin-1 to test its effects on angiogenesis, using unmodified and VVIAK modified silk fibroin hydrogel as controls. In monocultures of OECs, no angiogenic structures were observed in silk fibroin hydrogels. In contrast, vascular structures were abundant and increased in co-culture, as confirmed by immunocytochemistry and scanning electron microscopy (SEM) over 10 d of culture in silk fibroin-based hydrogels. Although no significant differences in angiogenic activity seem to be caused by the IKVAV peptide in our experimental settings, these results indicate that sonication-induced silk fibroin-based hydrogels support the formation of functional endothelial tubes and vascularization networks in the presence of mesenchymal cells supporting the vascular sprouting of endothelial cells. PMID:27271291

  12. CD133+ ovarian cancer stem-like cells promote non-stem cancer cell metastasis via CCL5 induced epithelial-mesenchymal transition

    PubMed Central

    Qi, Wei; Huang, Jiani; Chen, Junying; He, Luhang; Liang, Zhiqing; Guo, Bo; Li, Yongsheng; Xie, Rongkai; Zhu, Bo

    2015-01-01

    Cancer stem cells (CSCs, also called cancer stem-like cells, CSLCs) can function as “seed cells” for tumor recurrence and metastasis. Here, we report that, in the presence of CD133+ ovarian CSLCs, CD133− non-CSLCs can undergo an epithelial-mesenchymal transition (EMT)-like process and display enhanced metastatic capacity in vitro and in vivo. Highly elevated expression of chemokine (C-C motif) ligand 5 (CCL5) and its receptors chemokine (C-C motif) receptor (CCR) 1/3/5 are observed in clinical and murine metastatic tumor tissues from epithelial ovarian carcinomas. Mechanistically, paracrine CCL5 from ovarian CSLCs activates the NF-κB signaling pathway in ovarian non-CSLCs via binding CCR1/3/5, thereby inducing EMT and tumor invasion. Taken together, our results redefine the metastatic potential of non-stem cancer cells and provide evidence that targeting the CCL5:CCR1/3/5-NF-κB pathway could be an effective strategy to prevent ovarian cancer metastasis. PMID:25788271

  13. Promoting tumor penetration of nanoparticles for cancer stem cell therapy by TGF-β signaling pathway inhibition.

    PubMed

    Zuo, Zu-Qi; Chen, Kai-Ge; Yu, Xiao-Yuan; Zhao, Gui; Shen, Song; Cao, Zhi-Ting; Luo, Ying-Li; Wang, Yu-Cai; Wang, Jun

    2016-03-01

    Cancer stem cells (CSCs), which hold a high capacity for self-renewal, play a central role in the development, metastasis, and recurrence of various malignancies. CSCs must be eradicated to cure instances of cancer; however, because they can reside far from tumor vessels, they are not easily targeted by drug agents carried by nanoparticle-based drug delivery systems. We herein demonstrate that promoting tumor penetration of nanoparticles by transforming growth factor β (TGF-β) signaling pathway inhibition facilitates CSC therapy. In our study, we observed that although nanoparticles carrying siRNA targeting the oncogene polo-like kinase 1 (Plk1) efficiently killed breast CSCs derived from MDA-MB-231 cells in vitro, this intervention enriched CSCs in the residual tumor tissue following systemic treatment. However, inhibition of the TGF-β signaling pathway with LY364947, an inhibitor of TGF-β type I receptor, promoted the penetration of nanoparticles in tumor tissue, significantly ameliorating the intratumoral distribution of nanoparticles in MDA-MB-231 xenografts and further leading to enhanced internalization of nanoparticles by CSCs. As a result, synergistic treatment with a nanoparticle drug delivery system and LY364947 inhibited tumor growth and reduced the proportion of CSCs in vivo. This study suggests that enhanced tumor penetration of drug-carrying nanoparticles can enhance CSCs clearance in vivo and consequently provide superior anti-tumor effects. PMID:26751819

  14. Microvesicles Derived from Human Umbilical Cord Mesenchymal Stem Cells Stimulated by Hypoxia Promote Angiogenesis Both In Vitro and In Vivo

    PubMed Central

    Zhang, Hong-Chao; Liu, Xin-Bin; Huang, Shu; Bi, Xiao-Yun; Wang, Heng-Xiang; Xie, Li-Xian; Wang, Yong-Qi; Cao, Xiao-Fang; Lv, Jun; Xiao, Feng-Jun; Yang, Yang

    2012-01-01

    Although mesenchymal stem cells (MSCs) have been increasingly trialed to treat a variety of diseases, the underlying mechanisms remain still elusive. In this study, human umbilical cord (UC)-derived MSCs were stimulated by hypoxia, and the membrane microvesicles (MVs) in the supernatants were collected by ultracentrifugation, observed under an electron microscope, and the origin was identified with the flow cytometric technique. The results showed that upon hypoxic stimulus, MSCs released a large quantity of MVs of ∼100 nm in diameter. The MVs were phenotypically similar to the parent MSCs, except that the majority of them were negative for the receptor of platelet-derived growth factor. DiI-labeling assay revealed that MSC-MVs could be internalized into human UC endothelial cells (UC-ECs) within 8 h after they were added into the culture medium. Carboxyfluorescein succinimidyl ester-labeling technique and MTT test showed that MSC-MVs promoted the proliferation of UC-ECs in a dose-dependent manner. Further, MVs could enhance in vitro capillary network formation of UC-ECs in a Matrigel matrix. In a rat hindlimb ischemia model, both MSCs and MSC-MVs were shown to improve significantly the blood flow recovery compared with the control medium (P<0.0001), as assessed by laser Doppler imaging analysis. These data indicate that MV releasing is one of the major mechanisms underlying the effectiveness of MSC therapy by promoting angiogenesis. PMID:22839741

  15. Stem Cell Research.

    PubMed

    Trounson, Alan; Kolaja, Kyle; Petersen, Thomas; Weber, Klaus; McVean, Maralee; Funk, Kathleen A

    2015-01-01

    Stem cells have great potential in basic research and are being slowly integrated into toxicological research. This symposium provided an overview of the state of the field, stem cell models, described allogenic stem cell treatments and issues of immunogenicity associated with protein therapeutics, and tehn concentrated on stem cell uses in regenerative medicine focusing on lung and testing strategies on engineered tissues from a pathologist's perspective. PMID:25899720

  16. Information on Stem Cell Research

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS Information on Stem Cell Research Research @ NINDS Stem Cell Highlights Submit a hESC ... found here: Human Induced Pluripotent Stem Cells NINDS Stem Cell Research on Campus The Intramural Research Program of NINDS ...

  17. Hypoxia-induced secretion of IL-10 from adipose-derived mesenchymal stem cell promotes growth and cancer stem cell properties of Burkitt lymphoma.

    PubMed

    Xu, Lihua; Wang, Xu; Wang, Jiani; Liu, Dan; Wang, Yaya; Huang, Zhenqian; Tan, Huo

    2016-06-01

    In this study, we explored how the altered paracrine of adipose mesenchymal stem cells (ADSCs) contributed to the growth and cancer stem cell (CSC) properties of the Burkitt lymphoma cells. Condition mediums from normoxia or hypoxia cultured ADSC (CM-ADSC-N or CM-ADSC-H) were collected, and their effects on growth, colony formation, and apoptosis of Burkitt's lymphoma cells were investigated. Differentially expressed cytokines and inflammatory factors were compared between CM-ADSC-N and CM-ADSC-H. The involvement of differentially expressed IL-10 in growth and CSC properties of Burkitt lymphoma was investigated using both in vitro and in vivo models. Findings of this study showed that hypoxia increased IL-10 secretion from ADSCs, through which the growth and CSC properties of BL2 cells were enhanced. Intratumoral injection of CM-ADSC-H or IL-10 enhanced in vivo Burkitt lymphoma growth in nude mice model at least partly via the JAK2/STAT3 signaling pathway. PMID:26695151

  18. Induction of Split Anergy Conditions Natural Killer Cells to Promote Differentiation of Stem Cells through Cell–Cell Contact and Secreted Factors

    PubMed Central

    Tseng, Han-Ching; Bui, Vickie; Man, Yan-Gao; Cacalano, Nicholas; Jewett, Anahid

    2014-01-01

    In this paper, we provide evidence that anergized NK cells through secreted factors and direct cell–cell contact have the ability to induce differentiation of healthy dental pulp stem cells and stem cell of apical papillae as well as transformed oral squamous cancer stem cell (OSCSC) and Mia-Paca-2, poorly differentiated stem-like pancreatic tumors, resulting in their resistance to NK cell-mediated cytotoxicity. Induction of NK cell resistance and differentiation in the stem cells correlated with the increased expression of CD54, B7H1, and MHC class I, and mediated by the combination of membrane-bound or secreted IFN-γ and TNF-α from the NK cells since antibodies to both cytokines and not each one alone were able to inhibit differentiation or resistance to NK cells. Similarly, antibodies to both TNF-α and IFN-γ were required to prevent NK-mediated inhibition of cell growth, and restored the numbers of the stem cells to the levels obtained when stem cells were cultured in the absence of anergized NK cells. Interestingly, the effect of anti-IFN-γ antibody in the absence of anti-TNF-α antibody was more dominant for the prevention of increase in surface receptor expression since its addition abrogated the increase in CD54, B7H1, and MHC class I surface expression. Antibodies to CD54 or LFA-1 was unable to inhibit differentiation whereas antibodies to MHC class I but not B7H1 increased cytotoxicity of well-differentiated oral squamous carcinoma cells as well as OSCSCs differentiated by the IL-2 + anti-CD16 mAb-treated NK cells whereas it inhibited the cytotoxicity of NK cells against OSCSCs. Thus, NK cells may inhibit the progression of cancer by killing and/or differentiation of cancer stem cells, which severely halt cancer growth, invasion, and metastasis. PMID:24995006

  19. A Novel Combination of Factors, Termed SPIE, which Promotes Dopaminergic Neuron Differentiation from Human Embryonic Stem Cells

    PubMed Central

    Vazin, Tandis; Becker, Kevin G.; Chen, Jia; Spivak, Charles E.; Lupica, Carl R.; Zhang, Yongqing; Worden, Lila; Freed, William J.

    2009-01-01

    Background Stromal-Derived Inducing Activity (SDIA) is one of the most efficient methods of generating dopaminergic (DA) neurons from embryonic stem cells (ESC). DA neuron induction can be achieved by co-culturing ESC with the mouse stromal cell lines PA6 or MS5. The molecular nature of this effect, which has been termed “SDIA” is so far unknown. Recently, we found that factors secreted by PA6 cells provided lineage-specific instructions to induce DA differentiation of human ESC (hESC). Methodology/Principal Findings In the present study, we compared PA6 cells to various cell lines lacking the SDIA effect, and employed genome expression analysis to identify differentially-expressed signaling molecules. Among the factors highly expressed by PA6 cells, and known to be associated with CNS development, were stromal cell-derived factor 1 (SDF-1/CXCL12), pleiotrophin (PTN), insulin-like growth factor 2 (IGF2), and ephrin B1 (EFNB1). When these four factors, the combination of which was termed SPIE, were applied to hESC, they induced differentiation to TH-positive neurons in vitro. RT-PCR and western blot analysis confirmed the expression of midbrain specific markers, including engrailed 1, Nurr1, Pitx3, and dopamine transporter (DAT) in cultures influenced by these four molecules. Electrophysiological recordings showed that treatment of hESC with SPIE induced differentiation of neurons that were capable of generating action potentials and forming functional synaptic connections. Conclusions/Significance The combination of SDF-1, PTN, IGF2, and EFNB1 mimics the DA phenotype-inducing property of SDIA and was sufficient to promote differentiation of hESC to functional midbrain DA neurons. These findings provide a method for differentiating hESC to form DA neurons, without a requirement for the use of animal-derived cell lines or products. PMID:19672298

  20. Plant stem cell niches.

    PubMed

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis. PMID:22404469

  1. Loss of the Otx2-Binding Site in the Nanog Promoter Affects the Integrity of Embryonic Stem Cell Subtypes and Specification of Inner Cell Mass-Derived Epiblast.

    PubMed

    Acampora, Dario; Omodei, Daniela; Petrosino, Giuseppe; Garofalo, Arcomaria; Savarese, Marco; Nigro, Vincenzo; Di Giovannantonio, Luca Giovanni; Mercadante, Vincenzo; Simeone, Antonio

    2016-06-21

    Mouse embryonic stem cells (ESCs) and the inner cell mass (ICM)-derived epiblast exhibit naive pluripotency. ESC-derived epiblast stem cells (EpiSCs) and the postimplantation epiblast exhibit primed pluripotency. Although core pluripotency factors are well-characterized, additional regulators, including Otx2, recently have been shown to function during the transition from naive to primed pluripotency. Here we uncover a role for Otx2 in the control of the naive pluripotent state. We analyzed Otx2-binding activity in ESCs and EpiSCs and identified Nanog, Oct4, and Sox2 as direct targets. To unravel the Otx2 transcriptional network, we targeted the strongest Otx2-binding site in the Nanog promoter, finding that this site modulates the size of specific ESC-subtype compartments in cultured cells and promotes Nanog expression in vivo, predisposing ICM differentiation to epiblast. Otx2-mediated Nanog regulation thus contributes to the integrity of the ESC state and cell lineage specification in preimplantation development. PMID:27292645

  2. Stem Cells and Calcium Signaling

    PubMed Central

    Tonelli, Fernanda M.P.; Santos, Anderson K.; Gomes, Dawidson A.; da Silva, Saulo L.; Gomes, Katia N.; Ladeira, Luiz O.

    2014-01-01

    The increasing interest in stem cell research is linked to the promise of developing treatments for many lifethreatening, debilitating diseases, and for cell replacement therapies. However, performing these therapeutic innovations with safety will only be possible when an accurate knowledge about the molecular signals that promote the desired cell fate is reached. Among these signals are transient changes in intracellular Ca2+ concentration [Ca2+]i. Acting as an intracellular messenger, Ca2+ has a key role in cell signaling pathways in various differentiation stages of stem cells. The aim of this chapter is to present a broad overview of various moments in which Ca2+-mediated signaling is essential for the maintenance of stem cells and for promoting their development and differentiation, also focusing on their therapeutic potential. PMID:22453975

  3. Toward 'SMART' stem cells.

    PubMed

    Cheng, T

    2008-01-01

    Stem cell research is at the heart of regenerative medicine, which holds great promise for the treatment of many devastating disorders. However, in addition to hurdles posed by well-publicized ethical issues, this emerging field presents many biological challenges. What is a stem cell? How are embryonic stem cells different from adult stem cells? What are the physiological bases for therapeutically acceptable stem cells? In this editorial review, I will briefly discuss these superficially simple but actually rather complex issues that surround this fascinating cell type. The goal of this special issue on stem cells in Gene Therapy is to review some fundamental and critical aspects of current stem cell research that have translational potential. PMID:18046429

  4. Stem Cell Information: Glossary

    MedlinePlus

    ... based therapies Cell culture Cell division Chromosome Clone Cloning Cord blood stem cells Culture medium Differentiation Directed ... Pluripotent Polar body Preimplantation Proliferation Regenerative medicine Reproductive cloning Signals Somatic cell Somatic cell nuclear transfer (SCNT) ...

  5. Wound Dressing Model of Human Umbilical Cord Mesenchymal Stem Cells-Alginates Complex Promotes Skin Wound Healing by Paracrine Signaling

    PubMed Central

    Yang, Huachao; Tang, Zhenrui; Long, Gang; Huang, Wen

    2016-01-01

    Purpose. To probe growth characteristics of human umbilical cord mesenchymal stem cells (hUCMSCs) cultured with alginate gel scaffolds, and to explore feasibility of wound dressing model of hUCMSCs-alginates compound. Methods. hUCMSCs were isolated, cultured, and identified in vitro. Then cells were cultivated in 100 mM calcium alginate gel, and the capacity of proliferation and migration and the expression of vascular endothelial growth factors (VEGF) were investigated regularly. Wound dressing model of hUCMSCs-alginate gel mix was transplanted into Balb/c mice skin defects. Wound healing rate and immunohistochemistry were examined. Results. hUCMSCs grew well but with little migration ability in the alginate gel. Compared with control group, a significantly larger cell number and more VEGF expression were shown in the gel group after culturing for 3–6 days (P < 0.05). In addition, a faster skin wound healing rate with more neovascularization was observed in the hUCMSCs-alginate gel group than in control groups at 15th day after surgery (P < 0.05). Conclusion. hUCMSCs can proliferate well and express massive VEGF in calcium alginate gel porous scaffolds. Wound dressing model of hUCMSCs-alginate gel mix can promote wound healing through paracrine signaling. PMID:26880953

  6. Optimization of electrospun TSF nanofiber alignment and diameter to promote growth and migration of mesenchymal stem cells

    NASA Astrophysics Data System (ADS)

    Qu, Jing; Zhou, Dandan; Xu, Xiaojing; Zhang, Feng; He, Lihong; Ye, Rong; Zhu, Ziyu; Zuo, Baoqi; Zhang, Huanxiang

    2012-11-01

    Silk fibroin scaffolds are a naturally derived biocompatible matrix with the potential for reconstructive surgical applications. In this study, tussah silk fibroin (TSF) nanofiber with different diameters (400 nm, 800 nm and 1200 nm) and alignment (random and aligned) were prepared by electrospinning, then the growth and migration of mesenchymal stem cells (MSCs) on these materials were further evaluated. CD90 immunofluorescence staining showed that fiber alignment exhibited a strong influence on the morphology of MSCs, indicating that the alignment of the scaffolds could determine the distribution of cells. Moreover, smaller diameter and aligned TSF scaffolds are more favorable to the growth of MSCs as compared with 800 nm and 1200 nm random TSF scaffolds. In addition, the increased migration speed and efficiency of MSCs induced by three-D TSF were verified, highlighting the guiding roles of TSF to the migrated MSCs. More importantly, 400 nm aligned TSF scaffolds dramatically improved cell migratory speed and further induced the most efficient migration of MSCs as compared with larger diameter TSF scaffolds. In conclusion, the data demonstrate that smaller diameter and aligned electrospun TSF represent valuable scaffolds for supporting and promoting MSCs growth and migration, thus raising the possibility of manipulating TSF scaffolds to enhance homing and therapeutic potential of MSCs in cellular therapy.

  7. Ciliary Neurotrophic Factor Promotes the Migration of Corneal Epithelial Stem/progenitor Cells by Up-regulation of MMPs through the Phosphorylation of Akt.

    PubMed

    Chen, Jialin; Chen, Peng; Backman, Ludvig J; Zhou, Qingjun; Danielson, Patrik

    2016-01-01

    The migration of limbal epithelial stem cells is important for the homeostasis and regeneration of corneal epithelium. Ciliary neurotrophic factor (CNTF) has been found to promote corneal epithelial wound healing by activating corneal epithelial stem/progenitor cells. However, the possible effect of CNTF on the migration of corneal epithelial stem/progenitor cells is not clear. This study found the expression of CNTF in mouse corneal epithelial stem/progenitor cells (TKE2) to be up-regulated after injury, on both gene and protein level. CNTF promoted migration of TKE2 in a dose-dependent manner and the peak was seen at 10 ng/ml. The phosphorylation level of Akt (p-Akt), and the expression of MMP3 and MMP14, were up-regulated after CNTF treatment both in vitro and in vivo. Akt and MMP3 inhibitor treatment delayed the migration effect by CNTF. Finally, a decreased expression of MMP3 and MMP14 was observed when Akt inhibitor was applied both in vitro and in vivo. This study provides new insights into the role of CNTF on the migration of corneal epithelial stem/progenitor cells and its inherent mechanism of Up-regulation of matrix metalloproteinases through the Akt signalling pathway. PMID:27174608

  8. Ciliary Neurotrophic Factor Promotes the Migration of Corneal Epithelial Stem/progenitor Cells by Up-regulation of MMPs through the Phosphorylation of Akt

    PubMed Central

    Chen, Jialin; Chen, Peng; Backman, Ludvig J.; Zhou, Qingjun; Danielson, Patrik

    2016-01-01

    The migration of limbal epithelial stem cells is important for the homeostasis and regeneration of corneal epithelium. Ciliary neurotrophic factor (CNTF) has been found to promote corneal epithelial wound healing by activating corneal epithelial stem/progenitor cells. However, the possible effect of CNTF on the migration of corneal epithelial stem/progenitor cells is not clear. This study found the expression of CNTF in mouse corneal epithelial stem/progenitor cells (TKE2) to be up-regulated after injury, on both gene and protein level. CNTF promoted migration of TKE2 in a dose-dependent manner and the peak was seen at 10 ng/ml. The phosphorylation level of Akt (p-Akt), and the expression of MMP3 and MMP14, were up-regulated after CNTF treatment both in vitro and in vivo. Akt and MMP3 inhibitor treatment delayed the migration effect by CNTF. Finally, a decreased expression of MMP3 and MMP14 was observed when Akt inhibitor was applied both in vitro and in vivo. This study provides new insights into the role of CNTF on the migration of corneal epithelial stem/progenitor cells and its inherent mechanism of Up-regulation of matrix metalloproteinases through the Akt signalling pathway. PMID:27174608

  9. Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs

    SciTech Connect

    Zhou, Qiang; Zhao, Zhi-Ning; Cheng, Jing-Tao; Zhang, Bin; Xu, Jie; Huang, Fei; Zhao, Rui-Ni; Chen, Yong-Jin

    2011-01-07

    Research highlights: {yields} Ibandronate significantly promote the proliferation of PDLSC cells. {yields} Ibandronate enhanced the expression of ALP, COL-1, OPG, OCN, Runx2. {yields} The expression of a class of miRNAs, e.g., miR-18a, miR-133a, miR-141 and miR-19a, was significantly modified in PDLSC cells cultured with ibandronate. {yields} Ibandronate regulates the expression of diverse bone formation-related genes via miRNAs in PDLSCs. {yields} Ibandronate can suppress the activity of osteoclast while promoting the proliferation of osteoblast by regulating the expression of microRNAs. -- Abstract: Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation

  10. Runx2-Modified Adipose-Derived Stem Cells Promote Tendon Graft Integration in Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Zhang, Xin; Ma, Yong; Fu, Xin; Liu, Qiang; Shao, Zhenxing; Dai, Linghui; Pi, Yanbin; Hu, Xiaoqing; Zhang, Jiying; Duan, Xiaoning; Chen, Wenqing; Chen, Ping; Zhou, Chunyan; Ao, Yingfang

    2016-01-01

    Runx2 is a powerful osteo-inductive factor and adipose-derived stem cells (ADSCs) are multipotent. However, it is unknown whether Runx2-overexpressing ADSCs (Runx2-ADSCs) could promote anterior cruciate ligament (ACL) reconstruction. We evaluated the effect of Runx2-ADSCs on ACL reconstruction in vitro and in vivo. mRNA expressions of osteocalcin (OCN), bone sialoprotein (BSP) and collagen I (COLI) increased over time in Runx2-ADSCs. Runx2 overexpression inhibited LPL and PPARγ mRNA expressions. Runx2 induced alkaline phosphatase activity markedly. In nude mice injected with Runx2-ADSCs, promoted bone formation was detected by X-rays 8 weeks after injection. The healing of tendon-to-bone in a rabbit model of ACL reconstruction treated with Runx2-ADSCs, fibrin glue only and an RNAi targeting Runx2, was evaluated with CT 3D reconstruction, histological analysis and biomechanical methods. CT showed a greater degree of new bone formation around the bone tunnel in the group treated with Runx2-ADSCs compared with the fibrin glue group and RNAi Runx2 group. Histology showed that treatment with Runx2-ADSCs led to a rapid and significant increase at the tendon-to-bone compared with the control groups. Biomechanical tests demonstrated higher tendon pullout strength in the Runx2-ADSCs group at early time points. The healing of the attachment in ACL reconstruction was enhanced by Runx2-ADSCs. PMID:26743583

  11. Three-dimensional stress In vitro promotes the proliferation and differentiation of periodontal ligament stem cells implanted by bioactive glass.

    PubMed

    Wang, T; Li, G; Chen, J; Lin, Z; Qin, H; Ji, J

    2016-01-01

    To analyze the biological and mechanical microenvironment on the directional differentiation of periodontal ligament stem cells (PDLSCs) In vitro. PDLSCs were cultured in three-dimensional stress system In vitro for 1, 2 and 3 weeks. Methods like immunohistochemistry and flow cytometry were adopted and the proliferation and differentiation situation of PDLSCs were determined. Bioactive glass (BAG) of 0%, 10%, 20%, 30% and 40% was implanted into PDLSCs with or without three-dimensional stress for 3 weeks, respectively. The proliferation and differentiation situation of PDLSCs were determined. The mRNA levels of Alkaline phosphatase (ALP), Type I Collagen (COL I), Type II Collagen (COL II), Bone sialoprotein (BSP), Osteocalcin (OCN) and Osteopontin (OPN) were determined by semi-quantitative RT-PCR. 30% BAG and three-dimensional stress for 3 weeks promoted the proliferation and differentiation of PDLSCs mostly. PDLSCs induced by BAG and 3D force and the control all expressed the mRNA of ALP, COLⅠand COL Ⅱ. The BAG and three-dimensional stress induced PDLSCs also expressed the mRNA of BSP, OCN and OPN. BAG and three-dimensional stress indicated microenvironment In vitro can promote the proliferation and differentiation of PDLSCs. PMID:27609476

  12. The Drosophila BCL6 homolog Ken and Barbie promotes somatic stem cell self-renewal in the testis niche.

    PubMed

    Issigonis, Melanie; Matunis, Erika

    2012-08-15

    Stem cells sustain tissue regeneration by their remarkable ability to replenish the stem cell pool and to generate differentiating progeny. Signals from local microenvironments, or niches, control stem cell behavior. In the Drosophila testis, a group of somatic support cells called the hub creates a stem cell niche by locally activating the Janus Kinase-Signal Transducer and Activator of Transcription (JAK-STAT) pathway in two adjacent types of stem cells: germline stem cells (GSCs) and somatic cyst stem cells (CySCs). Here, we find that ken and barbie (ken) is autonomously required for the self-renewal of CySCs but not GSCs. Furthermore, Ken misexpression in the CySC lineage induces the cell-autonomous self-renewal of somatic cells as well as the nonautonomous self-renewal of germ cells outside the niche. Thus, Ken, like Stat92E and its targets ZFH1 (Leatherman and Dinardo, 2008) and Chinmo (Flaherty et al., 2010), is necessary and sufficient for CySC renewal. However, ken is not a JAK-STAT target in the testis, but instead acts in parallel to Stat92E to ensure CySC self-renewal. Ken represses a subset of Stat92E targets in the embryo (Arbouzova et al., 2006) suggesting that Ken maintains CySCs by repressing differentiation factors. In support of this hypothesis, we find that the global JAK-STAT inhibitor Protein tyrosine phosphatase 61F (Ptp61F) is a JAK-STAT target in the testis that is repressed by Ken. Together, our work demonstrates that Ken has an important role in the inhibition of CySC differentiation. Studies of ken may inform our understanding of its vertebrate orthologue B-Cell Lymphoma 6 (BCL6) and how misregulation of this oncogene leads to human lymphomas. PMID:22580161

  13. Growth Factors Cross-Linked to Collagen Microcarriers Promote Expansion and Chondrogenic Differentiation of Human Mesenchymal Stem Cells.

    PubMed

    Bertolo, Alessandro; Arcolino, Fanny; Capossela, Simona; Taddei, Anna Rita; Baur, Martin; Pötzel, Tobias; Stoyanov, Jivko

    2015-10-01

    Tissue engineering is a field in progressive expansion and requires constant updates in methods and devices. One of the central fields is the development of biocompatible, biodegradable, and injectable scaffolds, such as collagen microcarriers. To enhance cell attachment and produce a cost-effective cell culture solution with local stimulation of cells, basic fibroblast growth factor (bFGF) or transforming growth factor-β1 (TGF-β1) was covalently immobilized on microcarriers either by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) or riboflavin/UV (RB/UV) light-mediated cross-linking. Collagen microcarriers cross-linked with bFGF or TGF-β1 were used for expansion and chondrogenic differentiation of human mesenchymal stem cells (MSCs). Evaluation methods included cell viability test, chondrogenic marker expression (aggrecan and collagen type I and type II), histological detection of proteoglycans, and immunohistochemical analysis. Cross-linking strengthened the collagen structure of the microcarriers and reduced collagenase-mediated degradation. MSCs effectively proliferated on microcarriers cross-linked with bFGF, especially by EDC/NHS cross-linking. Chondrogenic differentiation of MSCs was induced by TGF-β1 cross-linked on microcarriers, promoting gene expression and protein accumulation of aggrecan and collagen type I and type II, as well as proteoglycans. Cross-linking by RB/UV enhanced chondrogenesis more than any other group. In addition, cross-linking reduced scaffold shrinkage exerted by MSCs during chondrogenesis, a desirable feature for microcarriers if used as tissue defect filler. In conclusion, cross-linking of bFGF or TGF-β1 to collagen microcarriers supported in vitro proliferation and chondrogenesis, respectively. If translated in vivo and in clinical practice, such approach might lead a step closer to development of a cost-effective and locally acting device for cell-based therapy. PMID:26222829

  14. Endothelial cell-fatty acid binding protein 4 promotes angiogenesis: role of stem cell factor/c-kit pathway.

    PubMed

    Elmasri, Harun; Ghelfi, Elisa; Yu, Chen-wei; Traphagen, Samantha; Cernadas, Manuela; Cao, Haiming; Shi, Guo-Ping; Plutzky, Jorge; Sahin, Mustafa; Hotamisligil, Gokhan; Cataltepe, Sule

    2012-09-01

    Fatty acid binding protein 4 (FABP4) plays an important role in regulation of glucose and lipid homeostasis as well as inflammation through its actions in adipocytes and macrophages. FABP4 is also expressed in a subset of endothelial cells, but its role in this cell type is not known. We found that FABP4-deficient human umbilical vein endothelial cells (HUVECs) demonstrate a markedly increased susceptibility to apoptosis as well as decreased migration and capillary network formation. Aortic rings from FABP4(-/-) mice demonstrated decreased angiogenic sprouting, which was recovered by reconstitution of FABP4. FABP4 was strongly regulated by mTORC1 and inhibited by Rapamycin. FABP4 modulated activation of several important signaling pathways in HUVECs, including downregulation of P38, eNOS, and stem cell factor (SCF)/c-kit signaling. Of these, the SCF/c-kit pathway was found to have a major role in attenuated angiogenic activity of FABP4-deficient ECs as provision of exogenous SCF resulted in a significant recovery in cell proliferation, survival, morphogenesis, and aortic ring sprouting. These data unravel a novel pro-angiogenic role for endothelial cell-FABP4 and suggest that it could be exploited as a potential target for diseases associated with pathological angiogenesis. PMID:22562362

  15. Endothelial cell-fatty acid binding protein 4 promotes angiogenesis: role of stem cell factor/c-kit pathway

    PubMed Central

    Elmasri, Harun; Ghelfi, Elisa; Yu, Chen-wei; Traphagen, Samantha; Cernadas, Manuela; Cao, Haiming; Shi, Guo-Ping; Plutzky, Jorge; Sahin, Mustafa; Hotamisligil, Gokhan; Cataltepe, Sule

    2013-01-01

    Fatty acid binding protein 4 (FABP4) plays an important role in regulation of glucose and lipid homeostasis as well as inflammation through its actions in adipocytes and macrophages. FABP4 is also expressed in a subset of endothelial cells, but its role in this cell type is not known. We found that FABP4-deficient human umbilical vein endothelial cells (HUVECs) demonstrate a markedly increased susceptibility to apoptosis as well as decreased migration and capillary network formation. Aortic rings from FABP4−/− mice demonstrated decreased angiogenic sprouting, which was recovered by reconstitution of FABP4. FABP4 was strongly regulated by mTORC1 and inhibited by Rapamycin. FABP4 modulated activation of several important signaling pathways in HUVECs, including downregulation of P38, eNOS, and stem cell factor (SCF)/c-kit signaling. Of these, the SCF/c-kit pathway was found to have a major role in attenuated angiogenic activity of FABP4-deficient ECs as provision of exogenous SCF resulted in a significant recovery in cell proliferation, survival, morphogenesis, and aortic ring sprouting. These data unravel a novel pro-angiogenic role for endothelial cell-FABP4 and suggest that it could be exploited as a potential target for diseases associated with pathological angiogenesis. PMID:22562362

  16. SQUINT promotes stem cell homeostasis and floral meristem termination in Arabidopsis through APETALA2 and CLAVATA signalling.

    PubMed

    Prunet, Nathanaël; Morel, Patrice; Champelovier, Priscilla; Thierry, Anne-Marie; Negrutiu, Ioan; Jack, Thomas; Trehin, Christophe

    2015-11-01

    Plant meristems harbour stem cells, which allow for the continuous production of new organs. Here, an analysis of the role of SQUINT (SQN) in stem cell dynamics in Arabidopsis is reported. A close examination of sqn mutants reveals defects that are very similar to that of weak clavata (clv) mutants, both in the flower meristem (increased number of floral organs, occasional delay in stem cell termination) and in the shoot apical meristem (meristem and central zone enlargement, occasional fasciation). sqn has a very mild effect in a clv mutant background, suggesting that SQN and the CLV genes act in the same genetic pathway. Accordingly, a loss-of-function allele of SQN strongly rescues the meristem abortion phenotype of plants that overexpress CLV3. Altogether, these data suggest that SQN is necessary for proper CLV signalling. SQN was shown to be required for normal accumulation of various miRNAs, including miR172. One of the targets of miR172, APETALA2 (AP2), antagonizes CLV signalling. The ap2-2 mutation strongly suppresses the meristem phenotypes of sqn, indicating that the effect of SQN on stem cell dynamics is largely, but not fully, mediated by the miR172/AP2 tandem. This study refines understanding of the intricate genetic networks that control both stem cell homeostasis and floral stem cell termination, two processes that are critical for the proper development and fertility of the plant. PMID:26269626

  17. Optimizing stem cell culture.

    PubMed

    van der Sanden, Boudewijn; Dhobb, Mehdi; Berger, François; Wion, Didier

    2010-11-01

    Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such as serum or feeder cell layers by recombinant cytokines or growth factors. Another example is the control of the oxygen pressure. For many years cell cultures have been done under atmospheric oxygen pressure which is much higher than the one experienced by stem cells in vivo. A consequence of cell metabolism is that cell culture conditions are constantly changing. Therefore, the development of high sensitive monitoring processes and control algorithms is required for ensuring cell culture medium homeostasis. Stem cells also sense the physical constraints of their microenvironment. Rigidity, stiffness, and geometry of the culture substrate influence stem cell fate. Hence, nanotopography is probably as important as medium formulation in the optimization of stem cell culture conditions. Recent advances include the development of synthetic bioinformative substrates designed at the micro- and nanoscale level. On going research in many different fields including stem cell biology, nanotechnology, and bioengineering suggest that our current way to culture cells in Petri dish or flasks will soon be outdated as flying across the Atlantic Ocean in the Lindbergh's plane. PMID:20803548

  18. SLUG is required for SOX9 stabilization and functions to promote cancer stem cells and metastasis in human lung carcinoma.

    PubMed

    Luanpitpong, S; Li, J; Manke, A; Brundage, K; Ellis, E; McLaughlin, S L; Angsutararux, P; Chanthra, N; Voronkova, M; Chen, Y C; Wang, L; Chanvorachote, P; Pei, M; Issaragrisil, S; Rojanasakul, Y

    2016-06-01

    Cancer stem cells (CSCs) are a promising target for cancer therapy, particularly for metastatic lung cancers, but how CSCs are regulated is largely unknown. We identify two proteins, SLUG (encoded by SNAI2 gene) and SOX9, which are associated with advanced stage lung cancers and are implicated in the regulation of CSCs. Inhibition of either SLUG or SOX9 sufficiently inhibits CSCs in human lung cancer cells and attenuates experimental lung metastasis in a xenograft mouse model. Correlation between SLUG and SOX9 levels was observed remarkably, we therefore sought to explore their mechanistic relationship and regulation. SLUG, beyond its known function as an epithelial-mesenchymal transition transcription factor, was found to regulate SOX9 by controlling its stability via a post-translational modification process. SLUG interacts directly with SOX9 and prevents it from ubiquitin-mediated proteasomal degradation. SLUG expression and binding are necessary for SOX9 promotion of lung CSCs and metastasis in a mouse model. Together, our findings provide a novel mechanistic insight into the regulation of CSCs via SLUG-SOX9 regulatory axis, which represents a potential novel target for CSC therapy that may overcome cancer chemoresistance and relapse. PMID:26387547

  19. Cancer Stem-like Cells Act via Distinct Signaling Pathways in Promoting Late Stages of Malignant Progression.

    PubMed

    da Silva-Diz, Victoria; Simón-Extremera, Pilar; Bernat-Peguera, Adrià; de Sostoa, Jana; Urpí, Maria; Penín, Rosa M; Sidelnikova, Diana Pérez; Bermejo, Oriol; Viñals, Joan Maria; Rodolosse, Annie; González-Suárez, Eva; Moruno, Antonio Gómez; Pujana, Miguel Ángel; Esteller, Manel; Villanueva, Alberto; Viñals, Francesc; Muñoz, Purificación

    2016-03-01

    Cancer stem-like cells (CSC) play key roles in long-term tumor propagation and metastasis, but their dynamics during disease progression are not understood. Tumor relapse in patients with initially excised skin squamous cell carcinomas (SCC) is characterized by increased metastatic potential, and SCC progression is associated with an expansion of CSC. Here, we used genetically and chemically-induced mouse models of skin SCC to investigate the signaling pathways contributing to CSC function during disease progression. We found that CSC regulatory mechanisms change in advanced SCC, correlating with aggressive tumor growth and enhanced metastasis. β-Catenin and EGFR signaling, induced in early SCC CSC, were downregulated in advanced SCC. Instead, autocrine FGFR1 and PDGFRα signaling, which have not been previously associated with skin SCC CSC, were upregulated in late CSC and promoted tumor growth and metastasis, respectively. Finally, high-grade and recurrent human skin SCC recapitulated the signaling changes observed in advanced mouse SCC. Collectively, our findings suggest a stage-specific switch in CSC regulation during disease progression that could be therapeutically exploited by targeting the PDGFR and FGFR1 pathways to block relapse and metastasis of advanced human skin SCC. PMID:26719534

  20. Injectable hydrogel promotes early survival of induced pluripotent stem cell-derived oligodendrocytes and attenuates longterm teratoma formation in a spinal cord injury model.

    PubMed

    Führmann, T; Tam, R Y; Ballarin, B; Coles, B; Elliott Donaghue, I; van der Kooy, D; Nagy, A; Tator, C H; Morshead, C M; Shoichet, M S

    2016-03-01

    Transplantation of pluripotent stem cells and their differentiated progeny has the potential to preserve or regenerate functional pathways and improve function after central nervous system injury. However, their utility has been hampered by poor survival and the potential to form tumors. Peptide-modified biomaterials influence cell adhesion, survival and differentiation in vitro, but their effectiveness in vivo remains uncertain. We synthesized a peptide-modified, minimally invasive, injectable hydrogel comprised of hyaluronan and methylcellulose to enhance the survival and differentiation of human induced pluripotent stem cell-derived oligodendrocyte progenitor cells. Cells were transplanted subacutely after a moderate clip compression rat spinal cord injury. The hydrogel, modified with the RGD peptide and platelet-derived growth factor (PDGF-A), promoted early survival and integration of grafted cells. However, prolific teratoma formation was evident when cells were transplanted in media at longer survival times, indicating that either this cell line or the way in which it was cultured is unsuitable for human use. Interestingly, teratoma formation was attenuated when cells were transplanted in the hydrogel, where most cells differentiated to a glial phenotype. Thus, this hydrogel promoted cell survival and integration, and attenuated teratoma formation by promoting cell differentiation. PMID:26773663

  1. Stem cell facelift: between reality and fiction.

    PubMed

    Atiyeh, Bishara S; Ibrahim, Amir E; Saad, Dibo A

    2013-03-01

    Stem cells are "big business" throughout medical technology, and their potential application in cosmetic procedures is no exception. One of the latest nonsurgical facial treatments (and new catchphrases) in plastic surgery is the "stem cell facelift." It is evident from the currently available scientific literature that the use of stem cell therapy for facial rejuvenation is limited to the theoretical induction of skin tightening and can in no way be equated to a facelift. In fact, what is advertised and promoted as a new and original technique of stem cell facelifting is mostly stem cell-enriched lipofilling. Despite encouraging data suggesting that adult stem cells hold promise for future applications, the data from clinical evidence available today do not substantiate the marketing and promotional claims being made to patients. To claim that the "stem cell facelift" is a complete facial rejuvenation procedure surgery is unethical. PMID:23417722

  2. Activin, BMP and FGF pathways cooperate to promote endoderm and pancreatic lineage cell differentiation from human embryonic stem cells.

    PubMed

    Xu, Xiaofang; Browning, Victoria L; Odorico, Jon S

    2011-01-01

    The study of how human embryonic stem cells (hESCs) differentiate into insulin-producing beta cells has twofold significance: first, it provides an in vitro model system for the study of human pancreatic development, and second, it serves as a platform for the ultimate production of beta cells for transplantation into patients with diabetes. The delineation of growth factor interactions regulating pancreas specification from hESCs in vitro is critical to achieving these goals. In this study, we describe the roles of growth factors bFGF, BMP4 and Activin A in early hESC fate determination. The entire differentiation process is carried out in serum-free chemically-defined media (CDM) and results in reliable and robust induction of pancreatic endoderm cells, marked by PDX1, and cell clusters co-expressing markers characteristic of beta cells, including PDX1 and insulin/C-peptide. Varying the combinations of growth factors, we found that treatment of hESCs with bFGF, Activin A and BMP4 (FAB) together for 3-4days resulted in strong induction of primitive-streak and definitive endoderm-associated genes, including MIXL1, GSC, SOX17 and FOXA2. Early proliferative foregut endoderm and pancreatic lineage cells marked by PDX1, FOXA2 and SOX9 expression are specified in EBs made from FAB-treated hESCs, but not from Activin A alone treated cells. Our results suggest that important tissue interactions occur in EB-based suspension culture that contribute to the complete induction of definitive endoderm and pancreas progenitors. Further differentiation occurs after EBs are embedded in Matrigel and cultured in serum-free media containing insulin, transferrin, selenium, FGF7, nicotinamide, islet neogenesis associated peptide (INGAP) and exendin-4, a long acting GLP-1 agonist. 21-28days after embedding, PDX1 gene expression levels are comparable to those of human islets used for transplantation, and many PDX1(+) clusters are formed. Almost all cells in PDX1(+) clusters co

  3. PLZF-Induced Upregulation of CXCR4 Promotes Dairy Goat Male Germline Stem Cell Proliferation by Targeting Mir146a.

    PubMed

    Mu, Hailong; Li, Na; Wu, Jiang; Zheng, Liming; Zhai, Yuanxin; Li, Bo; Song, Wencong; Wang, Jinglu; Zhu, Haijing; Li, Guangpeng; Hua, Jinlian

    2016-04-01

    Previous studies have shown that promyelocytic leukemia zinc finger (PLZF), chemokine (C-X-C motif) receptor 4 (CXCR4) and mir146a were associated with the self-renewal of mouse spermatogonial stem cells (SSCs); however, there is little information on their effects on the fate of livestock SSCs. Here, we have identified a regulatory pathway in dairy goat mGSCs, involving PLZF, mir146a and the SDF-1 receptor CXCR4. PLZF overexpression downregulated mir146a and simultaneously upregulated the expression of CXCR4 protein, whereas PLZF knockdown (siPLZF) induced the specifically opposite effects. The in vitro assays demonstrated that PLZF specifically interacts with and suppresses the mir146a promoter, and mir146a targets CXCR4 to impede its translation. The levels of ERK1/2 phosphorylation in the mGSCs overexpressed CXCR4 and PLZF were upregulated, respectively, whereas mir146a expression was decreased and CXCR4 protein was increased. Mir146a overexpression and siPLZF impaired mGSC proliferation and differentiation, however, Mir146a knockdown induced the opposite effects. The effects of PLZF and mir146a were mediated regulation by mir146a and CXCR4, respectively. Overexpression of CXCR4 or addition of CXCL12 in cultures of dairy goat mGSCs resulted in the upregulation of their signaling, and the phosphorylation of ERK1/2 was increased. Collectively, these findings indicate that PLZF is an important transcription factor in the regulation of the expression of CXCR4 to promote dairy goat mGSC proliferation by targeting mir146a. J. Cell. Biochem. 117: 844-852, 2016. © 2015 Wiley Periodicals, Inc. PMID:26365432

  4. Transforming growth factor-β1 promotes homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury

    PubMed Central

    Si, Xiaoyun; Liu, Ximing; Li, Jingjing; Wu, Xiaoyan

    2015-01-01

    Backgrounds: Acute ischemia reperfusion-induced kidney injury is a common cause of acute renal failure, and it is also an important cause of delayed recovery of transplanted kidney functions and even loss of function. However, there is no effective treatment method in clinical applications presently. Objective: The objective was to investigate effects of transforming growth factor-β1 on homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury. Methods: Effects of TGF-β1 over-expression in MSCs on expression of CXCR4 and chemotactic effect to SDF-1 were investigated by in vitro transmembrane chemotaxis. Anti-TGF-β1 antibody was incubated with ischemia reperfusion injury renal tissue homogenate and effects of anti-TGF-β1 antibody were observed. In addition, effects of TGF-β1 gene transfection and anti-CXCR4 antibody treatment in MSCs on expression of SDF-1/CXCR4 axis of renal tissues and damage repair were further explored. Results: Expression of TGF-β1 mRNA in the IRI group increased significantly, and MSCs transplantation could enhance expression of CXCR4 mRNA in rats of the IRI group, the expression of CXCR4 can be decreased by the anti-TGF-β1 antibody and the anti-CXCR4 antibody. TGF-β1 induced homing of MSCs in repair of renal ischemic reperfusion injury by regulating expression of CXCR4 on cell membranes. Blue fluorescence of DAPI-positive MSCs cells of renal parenchyma in the IRI+MSC group was enhanced significantly, which was significantly inhibited by anti-TGF-β1 and anti-CXCR4 antibody, and the inhibitory effect of anti-CXCR4 antibody was more obvious than that of anti-TGF-β1 antibody. Conclusion: Transforming growth factor-β1 promotes homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury, which will provide useful data on role of TGF-β1 in regulating SDF-1/CXCR4 axis-induced MSCs homing. PMID:26722423

  5. Platelet-Rich Plasma Promotes the Proliferation of Human Muscle Derived Progenitor Cells and Maintains Their Stemness

    PubMed Central

    Li, Hongshuai; Usas, Arvydas; Poddar, Minakshi; Chen, Chien-Wen; Thompson, Seth; Ahani, Bahar; Cummins, James; Lavasani, Mitra; Huard, Johnny

    2013-01-01

    Human muscle-derived progenitor cells (hMDPCs) offer great promise for muscle cell-based regenerative medicine; however, prolonged ex-vivo expansion using animal sera is necessary to acquire sufficient cells for transplantation. Due to the risks associated with the use of animal sera, the development of a strategy for the ex vivo expansion of hMDPCs is required. The purpose of this study was to investigate the efficacy of using platelet-rich plasma (PRP) for the ex-vivo expansion of hMDPCs. Pre-plated MDPCs, myoendothelial cells, and pericytes are three populations of hMDPCs that we isolated by the modified pre-plate technique and Fluorescence Activated Cell Sorting (FACS), respectively. Pooled allogeneic human PRP was obtained from a local blood bank, and the effect that thrombin-activated PRP-releasate supplemented media had on the ex-vivo expansion of the hMDPCs was tested against FBS supplemented media, both in vitro and in vivo. PRP significantly enhanced short and long-term cell proliferation, with or without FBS supplementation. Antibody-neutralization of PDGF significantly blocked the mitogenic/proliferative effects that PRP had on the hMDPCs. A more stable and sustained expression of markers associated with stemness, and a decreased expression of lineage specific markers was observed in the PRP-expanded cells when compared with the FBS-expanded cells. The in vitro osteogenic, chondrogenic, and myogenic differentiation capacities of the hMDPCs were not altered when expanded in media supplemented with PRP. All populations of hMDPCs that were expanded in PRP supplemented media retained their ability to regenerate myofibers in vivo. Our data demonstrated that PRP promoted the proliferation and maintained the multi-differentiation capacities of the hMDPCs during ex-vivo expansion by maintaining the cells in an undifferentiated state. Moreover, PDGF appears to be a key contributing factor to the beneficial effect that PRP has on the proliferation of hMDPCs. PMID

  6. The use of biomaterials for cell function enhancement: acceleration of fibroblast migration and promotion of stem cell proliferation

    NASA Astrophysics Data System (ADS)

    Qin, Sisi

    , while remained constant for the cells on the flat surfaces. The increased speed on the 8microm fiber surfaces could be correlated with a 20% increase in the nuclear deformation, and a decrease around 30% in the number of focal adhesion during the same observation period. RNA expression of Myosin IIA, a protein which complexes to the actin and is responsible for exertion of traction forces during migration was not upregulated during this process. On the other hand, histochemical staining of Myosin IIA showed that the protein had re-organized into large fibers which spanned the length of the cells. Observation of the cell morphology indicated that a new mode of motion had been established. Rather than the classical retraction of the cytoplasm followed by center of mass translation, which was observed on the flat surfaces, the cells were now moving by a contractile motion around the nucleus similar to that found in muscular motion. This mode was found to be more efficient when undergoing oriented motion. In addition to orientation, surface mechanics are also important in the tissue regeneration process. This study demonstrated that mechanical factors are important for the maintenance of pluripotency and control of proliferation rates. CD34+ hematopoietic stem cells (HSCs) were transduced with ICD (intracellular domain)-Notch and plated on gelatin hydrogels, whose moduli were controlled by the crosslinking ratio. On the softer hydrogel, a synergy was achieved which resulted in more than a five-fold increase in proliferation and a four-fold increase in the preservation of stemness, while HSCs maintained their ability to differentiate into multiple blood cell lineages. These results point the way for achieving clinically significant expansion of human HSCs.

  7. Histone Demethylase Expression Enhances Human Somatic Cell Nuclear Transfer Efficiency and Promotes Derivation of Pluripotent Stem Cells.

    PubMed

    Chung, Young Gie; Matoba, Shogo; Liu, Yuting; Eum, Jin Hee; Lu, Falong; Jiang, Wei; Lee, Jeoung Eun; Sepilian, Vicken; Cha, Kwang Yul; Lee, Dong Ryul; Zhang, Yi

    2015-12-01

    The extremely low efficiency of human embryonic stem cell (hESC) derivation using somatic cell nuclear transfer (SCNT) limits its potential application. Blastocyst formation from human SCNT embryos occurs at a low rate and with only some oocyte donors. We previously showed in mice that reduction of histone H3 lysine 9 trimethylation (H3K9me3) through ectopic expression of the H3K9me3 demethylase Kdm4d greatly improves SCNT embryo development. Here we show that overexpression of a related H3K9me3 demethylase KDM4A improves human SCNT, and that, as in mice, H3K9me3 in the human somatic cell genome is an SCNT reprogramming barrier. Overexpression of KDM4A significantly improves the blastocyst formation rate in human SCNT embryos by facilitating transcriptional reprogramming, allowing efficient derivation of SCNT-derived ESCs using adult Age-related Macular Degeneration (AMD) patient somatic nuclei donors. This conserved mechanistic insight has potential applications for improving SCNT in a variety of contexts, including regenerative medicine. PMID:26526725

  8. RBP2 induces stem-like cancer cells by promoting EMT and is a prognostic marker for renal cell carcinoma.

    PubMed

    Zhou, Dahai; Kannappan, Vinodh; Chen, Xiang; Li, Jingqin; Leng, Xuefeng; Zhang, Jinping; Xuan, Shiying

    2016-01-01

    Renal cell carcinoma (RCC), one of the most common kidney cancers, has a poor prognosis. Epithelial to mesenchymal transition (EMT) is a hallmark of carcinoma invasion and metastasis. Several studies have examined the molecular regulation of EMT, but the relationship between histone demethylases and EMT is little understood. In this study, we investigated the role of retinoblastoma-binding protein-2 (RBP2), a histone demethylase that is highly expressed in RCC and is positively correlated with poor RCC prognosis in the regulation of EMT. We found that ectopic overexpression of RBP2 can induce cancer stem cell-like (CSC) phenotypes through EMT in RCC cells by converting them to a more mesenchymal phenotype. This results in increased resistance to apoptosis, which leads to enhanced tumor growth in xenograft models. Together, our data show that RBP2 is an epigenetic regulator that has an important role in the initiation of CSC phenotypes through EMT, leading to tumor progression. RBP2 is also a novel biomolecule for RCC diagnosis, and prognosis and may be a therapeutic target. PMID:27282106

  9. RBP2 induces stem-like cancer cells by promoting EMT and is a prognostic marker for renal cell carcinoma

    PubMed Central

    Zhou, Dahai; Kannappan, Vinodh; Chen, Xiang; Li, Jingqin; Leng, Xuefeng; Zhang, Jinping; Xuan, Shiying

    2016-01-01

    Renal cell carcinoma (RCC), one of the most common kidney cancers, has a poor prognosis. Epithelial to mesenchymal transition (EMT) is a hallmark of carcinoma invasion and metastasis. Several studies have examined the molecular regulation of EMT, but the relationship between histone demethylases and EMT is little understood. In this study, we investigated the role of retinoblastoma-binding protein-2 (RBP2), a histone demethylase that is highly expressed in RCC and is positively correlated with poor RCC prognosis in the regulation of EMT. We found that ectopic overexpression of RBP2 can induce cancer stem cell-like (CSC) phenotypes through EMT in RCC cells by converting them to a more mesenchymal phenotype. This results in increased resistance to apoptosis, which leads to enhanced tumor growth in xenograft models. Together, our data show that RBP2 is an epigenetic regulator that has an important role in the initiation of CSC phenotypes through EMT, leading to tumor progression. RBP2 is also a novel biomolecule for RCC diagnosis, and prognosis and may be a therapeutic target. PMID:27282106

  10. Leukemia Stem Cell-Released Microvesicles Promote the Survival and Migration of Myeloid Leukemia Cells and These Effects Can Be Inhibited by MicroRNA34a Overexpression

    PubMed Central

    Wang, Yue; Cheng, Qian; Liu, Jing; Dong, Min

    2016-01-01

    Leukemia stem cells (LSCs) play the major role in relapse of acute myeloid leukemia (AML). Recent evidence indicates that microvesicles (MVs) released from cancer stem cells can promote tumor growth and invasion. In this study, we investigated whether LSCs-released MVs (LMVs) can regulate the malignance of AML cells and whether overexpression of tumor suppressive microRNA (miR), miR34a, is able to interrupt this process. LSCs were transfected with miRNA control (miRCtrl) or miR34a mimic for producing LMVs, respectively, defined as LMVsmiRCtrl and LMVsmiR34a. The effect of miR34a transfection on LSC proliferation and the effects of LMVsmiRCtrl or LMVsmiR34a on the proliferation, migration, and apoptosis of AML cells (after LSC depletion) were determined. The levels of miR34a targets, caspase-3 and T cell immunoglobulin mucin-3 (Tim-3), were analyzed. Results showed that (1) LMVsmiRCtrl promoted proliferation and migration and inhibited apoptosis of AML cells, which were associated with miR34a deficit; (2) transfection of miR34a mimic inhibited LSC proliferation and increased miR34a level in LMVsmiR34a; (3) LMVsmiR34a produced opposite effects as compared with LMVsmiRCtrl, which were associated with the changes of caspase-3 and Tim-3 levels. In summary, LMVs support AML cell malignance and modulating miR34a could offer a new approach for the management of AML. PMID:27127521

  11. Stress and stem cells.

    PubMed

    Tower, John

    2012-01-01

    The unique properties and functions of stem cells make them particularly susceptible to stresses and also lead to their regulation by stress. Stem cell division must respond to the demand to replenish cells during normal tissue turnover as well as in response to damage. Oxidative stress, mechanical stress, growth factors, and cytokines signal stem cell division and differentiation. Many of the conserved pathways regulating stem cell self-renewal and differentiation are also stress-response pathways. The long life span and division potential of stem cells create a propensity for transformation (cancer) and specific stress responses such as apoptosis and senescence act as antitumor mechanisms. Quiescence regulated by CDK inhibitors and a hypoxic niche regulated by FOXO transcription factor function to reduce stress for several types of stem cells to facilitate long-term maintenance. Aging is a particularly relevant stress for stem cells, because repeated demands on stem cell function over the life span can have cumulative cell-autonomous effects including epigenetic dysregulation, mutations, and telomere erosion. In addition, aging of the organism impairs function of the stem cell niche and systemic signals, including chronic inflammation and oxidative stress. PMID:23799624

  12. Adipose tissue-derived stem cells promote the reversion of non-alcoholic fatty liver disease: An in vivo study.

    PubMed

    Liao, Naishun; Pan, Fan; Wang, Yingchao; Zheng, Youshi; Xu, Bo; Chen, Wenwei; Gao, Yunzhen; Cai, Zhixiong; Liu, Xiaolong; Liu, Jingfeng

    2016-05-01

    Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver injury and seriously affects human health. In the present study, we aimed to investigate whether adipose tissue-derived stem cell (ADSC) transplantation in combination with dietary modification was capable of reversing the progression of NAFLD. After establishing a rat model of NAFLD by feeding them a high-fat diet (HFD), ADSCs were transplanted via the portal vein into rats with HFD-induced NAFLD, and simultaneously fed a modified diet. Thereafter, gross liver morphology, the hepatosomatic (HSI) index and indicators of liver function, including alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) were evaluated. Subsequently, the serum levels of total cholesterol (TC), triglycerides (TGs) and fatty acids (FAs) were also assayed. Furthermore, H&E and oil red O staining were used to confirm the pathological effects of NAFLD in the rat livers. Although dietary modification alone caused liver function to recover, ADSC transplantation in combination with dietary modification further decreased the HSI index, the serum levels of ALT, TBIL, TC, TGs, FAs, reduced lipid accumulation to normal levels, and reversed the hepatic pathological changes in the rat livers. Taken together, these findings suggest that ADSC transplantation assists in the reversion of NAFLD by improving liver function and promoting lipid metabolism, thereby exerting hepatoprotective effects. Thus, we suggest that ADSC transplantation is a promising, potential therapeutic strategy for NAFLD treatment. PMID:26986083

  13. MEK1 signaling promotes self-renewal and tumorigenicity of liver cancer stem cells via maintaining SIRT1 protein stabilization

    PubMed Central

    Cheng, Jiamin; Liu, Chungang; Liu, Limei; Chen, Xuejiao; Shan, Juanjuan; Shen, Junjie; Zhu, Wei; Qian, Cheng

    2016-01-01

    Hepatocellular carcinoma (HCC) is the third leading cause of cancer death. This high mortality has been commonly attributed to the presence of residual cancer stem cells (CSCs). Meanwhile, MEK1 signaling is regarded as a key molecular in HCC maintenance and development. However, nobody has figured out the particular mechanisms that how MEK1 signaling regulates liver CSCs self-renewal. In this study, we show that inhibition or depletion of MEK1 can significantly decrease liver CSCs self-renewal and tumor growth both in vitro and vivo conditions. Furthermore, we demonstrate that MEK1 signaling promotes liver CSCs self-renewal and tumorigenicity by maintaining SIRT1 level. Mechanistically, MEK1 signaling keeps SIRT1 protein stabilization through activating SIRT1 ubiquitination, which inhibits proteasomal degradation. Clinical analysis shows that patients co-expression of MEK1 and SIRT1 are associated with poor survival. Our finding indicates that MEK1-SIRT1 can act as a novel diagnostic biomarker and inhibition of MEK1 may be a viable therapeutic option for targeting liver CSCs treatment. PMID:26967560

  14. Adipose-Derived Stem Cells Expressing the Neurogenin-2 Promote Functional Recovery After Spinal Cord Injury in Rat.

    PubMed

    Tang, Linjun; Lu, Xiaocheng; Zhu, Ronglan; Qian, Tengda; Tao, Yi; Li, Kai; Zheng, Jinyu; Zhao, Penglai; Li, Shuai; Wang, Xi; Li, Lixin

    2016-07-01

    Neurogenin2 (Ngn2) is a proneural gene that directs neuronal differentiation of progenitor cells during development. This study aimed to investigate whether the use of adipose-derived stem cells (ADSCs) over-expressing the Ngn2 transgene (Ngn2-ADSCs) could display the characteristics of neurogenic cells and improve functional recovery in an experimental rat model of SCI. ADSCs from rats were cultured and purified in vitro, followed by genetically modified with the Ngn2 gene. Forty-eight adult female Sprague-Dawley rats were randomly assigned to three groups: the control, ADSCs, and Ngn2-ADSCs groups. The hind-limb motor function of all rats was recorded using the Basso, Beattie, and Bresnahan locomotor rating scale for 8 weeks. Moreover, hematoxylineosin staining and immunohistochemistry were also performed. After neural induction, positive expression rate of NeuN in Ngn2-ADSCs group was upon 90 %. Following transplantation, a great number of ADSCs was found around the center of the injury spinal cord at 1 and 4 weeks, which improved retention of tissue at the lesion site. Ngn2-ADSCs differentiated into neurons, indicated by the expression of neuronal markers, NeuN and Tuj1. Additionally, transplantation of Ngn2-ADSCs upregulated the trophic factors (brain-derived neurotrophic factor and vascular endothelial growth factor), and inhibited the glial scar formation, which was indicated by immunohistochemistry with glial fibrillary acidic protein. Finally, Ngn2-ADSCs-treated animals showed the highest functional recovery among the three groups. These findings suggest that transplantation of Ngn2-overexpressed ADSCs promote the functional recovery from SCI, and improve the local microenvironment of injured cord in a more efficient way than that with ADSCs alone. PMID:26283493

  15. Conserved dopamine neurotrophic factor-transduced mesenchymal stem cells promote axon regeneration and functional recovery of injured sciatic nerve.

    PubMed

    Liu, Yi; Nie, Lin; Zhao, Hua; Zhang, Wen; Zhang, Yuan-Qiang; Wang, Shuai-Shuai; Cheng, Lei

    2014-01-01

    Peripheral nerve injury (PNI) is a common disease that often results in axonal degeneration and the loss of neurons, ultimately leading to limited nerve regeneration and severe functional impairment. Currently, there are no effective treatments for PNI. In the present study, we transduced conserved dopamine neurotrophic factor (CDNF) into mesenchymal stem cells (MSCs) in collagen tubes to investigate their regenerative effects on rat peripheral nerves in an in vivo transection model. Scanning electron microscopy of the collagen tubes demonstrated their ability to be resorbed in vivo. We observed notable overexpression of the CDNF protein in the distal sciatic nerve after application of CDNF-MSCs. Quantitative analysis of neurofilament 200 (NF200) and S100 immunohistochemistry showed significant enhancement of axonal and Schwann cell regeneration in the group receiving CDNF-MSCs (CDNF-MSCs group) compared with the control groups. Myelination thickness, axon diameter and the axon-to fiber diameter ratio (G-ratio) were significantly higher in the CDNF-MSCs group at 8 and 12 weeks after nerve transection surgery. After surgery, the sciatic functional index, target muscle weight, wet weight ratio of gastrocnemius muscle and horseradish peroxidase (HRP) tracing demonstrated functional recovery. Light and electron microscopy confirmed successful regeneration of the sciatic nerve. The greater numbers of HRP-labeled neuron cell bodies and increased sciatic nerve index values (SFI) in the CDNF-MSCs group suggest that CDNF exerts neuroprotective effects in vivo. We also observed higher target muscle weights and a significant improvement in muscle atrophism in the CDNF-MSCs group. Collectively, these findings indicate that CDNF gene therapy delivered by MSCs is capable of promoting nerve regeneration and functional recovery, likely because of the significant neuroprotective and neurotrophic effects of CDNF and the superior environment offered by MSCs and collagen tubes. PMID

  16. Conserved Dopamine Neurotrophic Factor-Transduced Mesenchymal Stem Cells Promote Axon Regeneration and Functional Recovery of Injured Sciatic Nerve

    PubMed Central

    Liu, Yi; Nie, Lin; Zhao, Hua; Zhang, Wen; Zhang, Yuan-Qiang; Wang, Shuai-Shuai; Cheng, Lei

    2014-01-01

    Peripheral nerve injury (PNI) is a common disease that often results in axonal degeneration and the loss of neurons, ultimately leading to limited nerve regeneration and severe functional impairment. Currently, there are no effective treatments for PNI. In the present study, we transduced conserved dopamine neurotrophic factor (CDNF) into mesenchymal stem cells (MSCs) in collagen tubes to investigate their regenerative effects on rat peripheral nerves in an in vivo transection model. Scanning electron microscopy of the collagen tubes demonstrated their ability to be resorbed in vivo. We observed notable overexpression of the CDNF protein in the distal sciatic nerve after application of CDNF-MSCs. Quantitative analysis of neurofilament 200 (NF200) and S100 immunohistochemistry showed significant enhancement of axonal and Schwann cell regeneration in the group receiving CDNF-MSCs (CDNF-MSCs group) compared with the control groups. Myelination thickness, axon diameter and the axon-to fiber diameter ratio (G-ratio) were significantly higher in the CDNF-MSCs group at 8 and 12 weeks after nerve transection surgery. After surgery, the sciatic functional index, target muscle weight, wet weight ratio of gastrocnemius muscle and horseradish peroxidase (HRP) tracing demonstrated functional recovery. Light and electron microscopy confirmed successful regeneration of the sciatic nerve. The greater numbers of HRP-labeled neuron cell bodies and increased sciatic nerve index values (SFI) in the CDNF-MSCs group suggest that CDNF exerts neuroprotective effects in vivo. We also observed higher target muscle weights and a significant improvement in muscle atrophism in the CDNF-MSCs group. Collectively, these findings indicate that CDNF gene therapy delivered by MSCs is capable of promoting nerve regeneration and functional recovery, likely because of the significant neuroprotective and neurotrophic effects of CDNF and the superior environment offered by MSCs and collagen tubes. PMID

  17. Dental stem cell patents.

    PubMed

    Morsczeck, Christian; Frerich, Bernhard; Driemel, Oliver

    2009-01-01

    A complex human tissue harbors stem cells that are responsible for its maintenance or repair. These stem cells have been isolated also from dental tissues such as the periodontal ligament, dental papilla or dental follicle and they may offer novel applications in dentistry. This following review summarizes patents about dental stem cells for dental tissue engineering and considers their value for regenerative dentistry. PMID:19149737

  18. A novel long non-coding RNA, hypoxia-inducible factor-2α promoter upstream transcript, functions as an inhibitor of osteosarcoma stem cells in vitro

    PubMed Central

    WANG, YONGCHENG; YAO, JIE; MENG, HAOYE; YU, ZHIGUO; WANG, ZHIGANG; YUAN, XUELING; CHEN, HONG; WANG, AIYUAN

    2015-01-01

    Long non-coding RNAs (lncRNAs) have recently been identified as novel modulators of malignant tumors. However, the function of lncRNAs in cancer stem cells (CSCs) remains to be elucidated. The present study aimed to investigate the regulating role of a novel lncRNA, hypoxia-inducible factor-2α (HIF-2α) promoter upstream transcript (HIF2PUT), in osteosarcoma stem cells. The expression levels of HIF2PUT were assessed by quantitative polymerase chain reaction in 17 osteosarcoma tissue specimens, and the correlation between the expression of HIF2PUT and its host transcript-HIF-2α was determined. In functional experiments, HIF2PUT expression was knocked down by small interfering RNAs, or overexpressed by transfection with pcDNA-HIF2PUT, in order to evaluate the effects of HIF2PUT on cell proliferation, migration, expression rate of osteosarcoma stem cell marker CD133, and stem sphere-forming ability in MG63 cells. HIF2PUT expression levels were positively correlated with HIF-2α in osteosarcoma tissues. Overexpression of HIF2PUT markedly inhibited cell proliferation and migration, decreased the percentage of CD133 expressing cells, and impaired the osteosarcoma stem sphere-forming ability of the MG63 cells. Whereas, knockdown of HIF2PUT expression had the opposite effect. Furthermore, altering the expression of HIF2PUT resulted in a concomitant change to HIF-2α mRNA expression. These results indicate that the lncRNA HIF2PUT may be a novel regulatory factor of osteosarcoma stem cells, which may exert its function partly by controlling HIF-2α expression. Further studies regarding HIF2PUT may provide a novel therapeutic target of osteosarcoma in the future. PMID:25434862

  19. The role of mesenchymal stem cells in promoting the transformation of androgen-dependent human prostate cancer cells into androgen-independent manner

    PubMed Central

    Cheng, Jiwen; Yang, Keqin; Zhang, Qingyun; Yu, Yang; Meng, Qinggui; Mo, Ning; Zhou, Yang; Yi, Xianlin; Ma, Chengzhong; Lei, Aming; Liu, Yan

    2016-01-01

    Mesenchymal stem cells (MSCs) play an important role in the development of human prostate cancer (PCa). However, the role of MSCs in the transformation of androgen-dependent human PCa cells into androgen-independent manner has been poorly understood. In this study, we investigated the underlying mechanism of MSCs in promoting PCa cells from androgen-dependent into androgen-independent manner. Firstly, we demonstrated that MSCs could affect the transformation of androgen-dependent human PCa cells into androgen-independent manner in vivo and in vitro. Then we found a substantial expression of TGF-β in MSCs. TGF-β blockade could significantly inhibit the promotive function of MSCs in PCa cells. Besides that, we also demonstrated androgen might inhibit the expression of TGF-β in MSCs. Furthermore, we found that either overexpression of SSEA-4 or the number of SSEA-4 positive MSCs in PCa tissues was associated with a shorter cancer-free survival interval (CFSI) and a worse overall survival (OS). Our results suggest that androgen blockade treatment in clinical PCa therapy may elicit the expression of TGF-β in MSCs, which will result in the transformation of androgen-dependent human PCa cells into androgen-independent manner. PMID:26787499

  20. Structured three-dimensional co-culture of mesenchymal stem cells with meniscus cells promotes meniscal phenotype without hypertrophy.

    PubMed

    Cui, Xiaofeng; Hasegawa, Akihiko; Lotz, Martin; D'Lima, Darryl

    2012-09-01

    Menisci play a crucial role in weight distribution, load bearing, shock absorption, lubrication, and nutrition of articular cartilage within the knee joint. Damage to the meniscus typically does not heal spontaneously due to its partial avascular nature. Partial or complete meniscectomy is a common clinical treatment of the defective meniscus. However, this procedure ultimately leads to osteoarthritis due to increased mechanical stress to the articular cartilage. Meniscus tissue engineering offers a promising solution for partial or complete meniscus deficiency. Mesenchymal stem cells (MSC) have the potential to differentiate into meniscal fibrochondrocyte as well as deliver trophic effects to the differentiated cells. This study tested the feasibility of using MSC co-cultured with mature meniscal cells (MC) for meniscus tissue engineering. Structured cell pellets were created using MC and MSC at varying ratios (100:0, 75:25, 50:50, 25:75, and 0:100) and cultured with or without transforming growth factor-beta 3 supplemented chondrogenic media for 21 days. The meniscal and hypertrophic gene expression, gross appearance and structure of the pellets, meniscus extracellular matrix (ECM), histology and immunohistochemistry of proteoglycan and collagen were evaluated. Co-culture of MC with MSC at 75:25 demonstrated highest levels of collagen type I and glycosaminoglycans (GAG) production, as well as the lowest levels of hypertrophic genes, such as COL10A1 and MMP13. All co-culture conditions showed better meniscus ECM production and hypertrophic inhibition as compared to MSC culture alone. The collagen fiber bundles observed in the co-cultures are important to produce heterogenic ECM structure of meniscus. In conclusion, co-culturing MC and MSC is a feasible and efficient approach to engineer meniscus tissue with enhanced ECM production without hypertrophy. PMID:22422555

  1. By promoting cell differentiation, miR-100 sensitizes basal-like breast cancer stem cells to hormonal therapy

    PubMed Central

    Cargnelutti, Marilisa; Iovino, Flora; Callari, Maurizio; Cimino, Daniela; Todaro, Matilde; Mangiapane, Laura Rosa; Giammona, Alessandro; Cordova, Adriana; Montemurro, Filippo; Taverna, Daniela; Daidone, Maria Grazia

    2015-01-01

    Basal-like breast cancer is an aggressive tumor subtype with a poor response to conventional therapies. Tumor formation and relapse are sustained by a cell subset of Breast Cancer Stem Cells (BrCSCs). Here we show that miR-100 inhibits maintenance and expansion of BrCSCs in basal-like cancer through Polo-like kinase1 (Plk1) down-regulation. Moreover, miR-100 favors BrCSC differentiation, converting a basal like phenotype into luminal. It induces the expression of a functional estrogen receptor (ER) and renders basal-like BrCSCs responsive to hormonal therapy. The key role played by miR-100 in breast cancer free-survival is confirmed by the analysis of a cohort of patients’ tumors, which shows that low expression of miR-100 is a negative prognostic factor and is associated with gene signatures of high grade undifferentiated tumors. Our findings indicate a new possible therapeutic strategy, which could make aggressive breast cancers responsive to standard treatments. PMID:25537513

  2. Sphingosylphosphorylcholine promotes the differentiation of resident Sca-1 positive cardiac stem cells to cardiomyocytes through lipid raft/JNK/STAT3 and β-catenin signaling pathways.

    PubMed

    Li, Wenjing; Liu, Honghong; Liu, Pingping; Yin, Deling; Zhang, Shangli; Zhao, Jing

    2016-07-01

    Resident cardiac Sca-1-positive (+) stem cells may differentiate into cardiomyocytes to improve the function of damaged hearts. However, little is known about the inducers and molecular mechanisms underlying the myogenic conversion of Sca-1(+) stem cells. Here we report that sphingosylphosphorylcholine (SPC), a naturally occurring bioactive lipid, induces the myogenic conversion of Sca-1(+) stem cells, as evidenced by the increased expression of cardiac transcription factors (Nkx2.5 and GATA4), structural proteins (cardiac Troponin T), transcriptional enhancer (Mef2c) and GATA4 nucleus translocation. First, SPC activated JNK and STAT3, and the JNK inhibitor SP600125 or STAT3 inhibitor stattic impaired the SPC-induced expression of cardiac transcription factors and GATA4 nucleus translocation, which suggests that JNK and STAT3 participated in SPC-promoted cardiac differentiation. Moreover, STAT3 activation was inhibited by SP600125, whereas JNK was inhibited by β-cyclodextrin as a lipid raft breaker, which indicates a lipid raft/JNK/STAT3 pathway involved in SPC-induced myogenic transition. β-Catenin, degraded by activated GSK3β, was inhibited by SPC. Furthermore, GSK3β inhibitors weakened but the β-catenin inhibitor promoted SPC-induced differentiation. We found no crosstalk between the lipid raft/JNK/STAT3 and β-catenin pathway. Our study describes a lipid, SPC, as an endogenic inducer of myogenic conversion in Sca-1(+) stem cells with low toxicity and high efficiency for uptake. PMID:27066979

  3. Fast and safe fabrication of a free-standing chitosan/alginate nanomembrane to promote stem cell delivery and wound healing

    PubMed Central

    Kong, Yi; Xu, Rui; Darabi, Mohammad Ali; Zhong, Wen; Luo, Gaoxing; Xing, Malcolm MQ; Wu, Jun

    2016-01-01

    Polymeric ultrathin membranes that are compatible with cells offer tremendous advantages for tissue engineering. In this article, we report a free-standing nanomembrane that was developed using a layer-by-layer self-assembly technique with a safe and sacrificial substrate method. After ionization, two oppositely charged polyelectrolytes, alginate and chitosan, were alternately deposited on a substrate of a solidified gelatin block to form an ultrathin nanomembrane. The space between the two adjacent layers was ∼200 nm. The thickness of the nanomembrane was proportional to the number of layers. The temperature-sensitive gelatin gel served as a sacrificial template at 37°C. The free-standing nanomembrane promoted bone marrow stem cell adhesion and proliferation. Fluorescence-activated cell sorting was used to analyze green-fluorescent-protein-positive mesenchymal stem cells from the wounds, which showed a significantly high survival and proliferation from the nanomembrane when cells were transplanted to mouse dorsal skin that had a full-thickness burn. The bone-marrow-stem-cell-loaded nanomembrane also accelerated wound contraction and epidermalization. Therefore, this methodology provides a fast and facile approach to construct free-standing ultrathin scaffolds for tissue engineering. The biocompatibility and free-standing nature of the fabricated nanomembrane may be particularly useful for stem cell delivery and wound healing. PMID:27354789

  4. Fast and safe fabrication of a free-standing chitosan/alginate nanomembrane to promote stem cell delivery and wound healing.

    PubMed

    Kong, Yi; Xu, Rui; Darabi, Mohammad Ali; Zhong, Wen; Luo, Gaoxing; Xing, Malcolm Mq; Wu, Jun

    2016-01-01

    Polymeric ultrathin membranes that are compatible with cells offer tremendous advantages for tissue engineering. In this article, we report a free-standing nanomembrane that was developed using a layer-by-layer self-assembly technique with a safe and sacrificial substrate method. After ionization, two oppositely charged polyelectrolytes, alginate and chitosan, were alternately deposited on a substrate of a solidified gelatin block to form an ultrathin nanomembrane. The space between the two adjacent layers was ∼200 nm. The thickness of the nanomembrane was proportional to the number of layers. The temperature-sensitive gelatin gel served as a sacrificial template at 37°C. The free-standing nanomembrane promoted bone marrow stem cell adhesion and proliferation. Fluorescence-activated cell sorting was used to analyze green-fluorescent-protein-positive mesenchymal stem cells from the wounds, which showed a significantly high survival and proliferation from the nanomembrane when cells were transplanted to mouse dorsal skin that had a full-thickness burn. The bone-marrow-stem-cell-loaded nanomembrane also accelerated wound contraction and epidermalization. Therefore, this methodology provides a fast and facile approach to construct free-standing ultrathin scaffolds for tissue engineering. The biocompatibility and free-standing nature of the fabricated nanomembrane may be particularly useful for stem cell delivery and wound healing. PMID:27354789

  5. The promotion of hepatic maturation of human pluripotent stem cells in 3D co-culture using type I collagen and Swiss 3T3 cell sheets.

    PubMed

    Nagamoto, Yasuhito; Tashiro, Katsuhisa; Takayama, Kazuo; Ohashi, Kazuo; Kawabata, Kenji; Sakurai, Fuminori; Tachibana, Masashi; Hayakawa, Takao; Furue, Miho Kusuda; Mizuguchi, Hiroyuki

    2012-06-01

    Hepatocyte-like cells differentiated from human embryonic stem cells (hESCs) or human induced pluripotent stem cells (hiPSCs) are known to be a useful cell source for drug screening. We recently developed an efficient hepatic differentiation method from hESCs and hiPSCs by sequential transduction of FOXA2 and HNF1α. It is known that the combination of three-dimensional (3D) culture and co-culture, namely 3D co-culture, can maintain the functions of primary hepatocytes. However, hepatic maturation of hESC- or hiPSC-derived hepatocyte-like cells (hEHs or hiPHs, respectively) by 3D co-culture systems has not been examined. Therefore, we utilized a cell sheet engineering technology to promote hepatic maturation. The gene expression levels of hepatocyte-related markers (such as cytochrome P450 enzymes and conjugating enzymes) and the amount of albumin secretion in the hEHs or hiPHs, which were 3D co-cultured with the Swiss 3T3 cell sheet, were significantly up-regulated in comparison with those in the hEHs or hiPHs cultured in a monolayer. Furthermore, we found that type I collagen synthesized in Swiss 3T3 cells plays an important role in hepatic maturation. The hEHs or hiPHs that were 3D co-cultured with the Swiss 3T3 cell sheet would be powerful tools for medical applications, such as drug screening. PMID:22445253

  6. Enhanced cell survival and paracrine effects of mesenchymal stem cells overexpressing hepatocyte growth factor promote cardioprotection in myocardial infarction.

    PubMed

    Zhao, Liyan; Liu, Xiaolin; Zhang, Yuelin; Liang, Xiaoting; Ding, Yue; Xu, Yan; Fang, Zhen; Zhang, Fengxiang

    2016-05-15

    Poor cell survival post transplantation compromises the therapeutic benefits of mesenchymal stem cells (MSCs) in myocardial infarction (MI). Hepatocyte growth factor (HGF) is an important cytokine for angiogenesis, anti-inflammation and anti-apoptosis. This study aimed to evaluate the cardioprotective effects of MSCs overexpressing HGF in a mouse model of MI. The apoptosis of umbilical cord-derived MSCs (UC-MSCs) and HGF-UC-MSCs under normoxic and hypoxic conditions was detected. The conditioned medium (CdM) of UC-MSCs and HGF-UC-MSCs under a hypoxic condition was harvested and its protective effect on neonatal cardiomyocytes (NCMs) exposed to a hypoxic challenge was examined. UC-MSCs and HGF-UC-MSCs were transplanted into the peri-infarct region in mice following MI and heart function assessed 4 weeks post transplantation. The apoptosis of HGF-UC-MSCs under hypoxic conditions was markedly decreased compared with that of UC-MSCs. NCMs treated with HGF-UC-MSC hypoxic CdM (HGF-UC-MSCs-hy-CdM) exhibited less cell apoptosis in response to hypoxic challenge than those treated with UC-MSC hypoxic CdM (UC-MSCs-hy-CdM). HGF-UC-MSCs-hy-CdM released the inhibited p-Akt and lowered the enhanced ratio of Bax/Bcl-2 induced by hypoxia in the NCMs. HGF-UC-MSCs-hy-CdM expressed higher levels of HGF, EGF, bFGF and VEGF than UC-MSCs-hy-CdM. Transplantation of HGF-UC-MSCs or UC-MSCs greatly improved heart function in the mouse model of MI. Compared with UC-MSCs, transplantation of HGF-UC-MSCs was associated with less cardiomyocyte apoptosis, enhanced angiogenesis and increased proliferation of cardiomyocytes. This study may provide a novel therapeutic strategy for MSC-based therapy in cardiovascular disease. PMID:27025401

  7. Notochordal conditioned media from tissue increases proteoglycan accumulation and promotes a healthy nucleus pulposus phenotype in human mesenchymal stem cells

    PubMed Central

    2011-01-01

    Introduction Notochordal cells (NCs) are influential in development of the intervertebral disc (IVD) and species that retain NCs do not degenerate. IVD repair using bone marrow derived mesenchymal stem cells (MSCs) is an attractive approach and the harsh microenvironment of the IVD suggests pre-differentiation is a necessary first step. The goal of this study was to use soluble factors from NCs in alginate and NCs in their native tissue to differentiate human MSCs to a young nucleus pulposus (NP) phenotype. Methods Human MSCs (cultured under micromass conditions for 21 days in hypoxia) were differentiated with conditioned medium derived from porcine notochordal cells in native tissue (NCT) or in alginate beads (NCA), and compared with chondrogenic (TGFβ-3) or basal medium. A PCR array of 42 genes was utilized to screen a large number of genes known to be associated with the healthy NP phenotype and pellet cultures were also evaluated for glycosaminoglycan content, histology and viability. Proteomic analysis was used to assess candidate soluble factors in NCA and NCT. Results Notochordal cell conditioned media had diverse effects on MSC phenotype. NCT resulted in the highest levels of glycosaminoglycan (GAG), as well as up-regulation of SOX9 and Collagen II gene expression. NCA demonstrated effects that were catabolic yet also anti-fibrotic and minimally hypertrophic with down-regulation of Collagens I and III and low levels of Collagen X, respectively. Micromass culture and hypoxic conditions were sufficient to promote chondrogenesis demonstrating that both basal and chondrogenic media produced similar phenotypes. Candidate matricellular proteins, clusterin and tenascin were identified by proteomics in the NCA group. Conclusions NCs secreted important soluble factors capable of differentiating MSCs to a NP phenotype synthesizing high levels of proteoglycan while also resisting collagen fiber expression and hypertrophy, yet results were sensitive to the conditions

  8. IGF-1R signaling is essential for the proliferation of cultured mouse spermatogonial stem cells by promoting the G2/M progression of the cell cycle.

    PubMed

    Wang, Si; Wang, Xiuxia; Wu, Yujian; Han, Chunsheng

    2015-02-15

    Culture of mouse spermatogonial stem cells (mSSCs) contributes to understanding the mechanisms of mammalian spermatogenesis. Several key growth factors such as GDNF and FGF2 have been known to be essential for the proliferation of cultured mSSCs. However, additional factors regulating SSC proliferation remain to be identified. In this study, we report that IGF-1R signaling is required for the proliferation of cultured mSSCs by promoting the G2/M progression of the cell cycle. IGF-1 and its receptor IGF-1R are expressed in cultured mSSCs as well as in isolated Sertoli cells and interstitial cells. Blockage of IGF-1R signaling either by knockdown of IGF-1R or by the IGF-1R-specific inhibitor picropodophyllin (PPP) significantly reduced the proliferation of mSSCs, increased their apoptosis, and impaired their stem cell activity in an insulin-independent manner. PPP treatment of mSSCs blocked the G2/M progression. In contrast, both GDNF withdrawal and FGF2 signaling blockade decreased the entry of mSSCs into their S phases. Consistently, IGF-1 promoted the G2/M progression of thymidine-treated mSSCs, which were arrested at G1/S boundary synchronously; while GDNF and/or FGF2 stimulated their entry into the S phase. Moreover, IGF-1 activated the phosphorylation of AKT but not that of ERK1/2 in mSSCs. These results indicate that IGF-1R signaling stimulates the proliferation of mSSCs using a distinct mechanism from those by GDNF and FGF2, and will contribute to the establishment of a chemically defined culture system. PMID:25356638

  9. Intraoperative Stem Cell Therapy

    PubMed Central

    Coelho, Mónica Beato; Cabral, Joaquim M.S.; Karp, Jeffrey M.

    2013-01-01

    Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the potential regenerative mechanisms and the roles of different cell populations in the regeneration process are discussed. Although intraoperative stem cell therapies have been shown to be safe and effective for several indications, there are still critical challenges to be tackled prior to adoption into the standard surgical armamentarium. PMID:22809140

  10. Promotion of cardiac differentiation of brown adipose derived stem cells by chitosan hydrogel for repair after myocardial infarction.

    PubMed

    Wang, Haibin; Shi, Jinxin; Wang, Yan; Yin, Yujing; Wang, Liman; Liu, Jianfeng; Liu, Zhiqiang; Duan, Cuimi; Zhu, Ping; Wang, Changyong

    2014-04-01

    The ability to restore heart function by replacement of diseased myocardium is one of the great challenges in biomaterials and regenerative medicine. Brown adipose derived stem cells (BADSCs) present a new source of cardiomyocytes to regenerate the myocardium after infarction. In this study, we explored an injectable tissue engineering strategy to repair damaged myocardium, in which chitosan hydrogels were investigated as a carrier for BADSCs. In vitro, the effect and mechanism of chitosan components on the cardiac differentiation of BADSCs were investigated. In vivo, BADSCs carrying double-fusion reporter gene (firefly luciferase and monomeric red fluorescent protein (fluc-mRFP)) were transplanted into infarcted rat hearts with or without chitosan hydrogel. Multi-techniques were used to assess the effects of treatments. We observed that chitosan components significantly enhanced cardiac differentiation of BADSCs, which was assessed by percentages of cTnT(+) cells and expression of cardiac-specific markers, including GATA-4, Nkx2.5, Myl7, Myh6, cTnI, and Cacna1a. Treatment with collagen synthesis inhibitors, cis-4-hydroxy-D-proline (CIS), significantly inhibited the chitosan-enhanced cardiac differentiation, indicating that the enhanced collagen synthesis by chitosan accounts for its promotive role in cardiac differentiation of BADSCs. Longitudinal in vivo bioluminescence imaging and histological staining revealed that chitosan enhanced the survival of engrafted BADSCs and significantly increased the differentiation rate of BADSCs into cardiomyocytes in vivo. Furthermore, BADSCs delivered by chitosan hydrogel prevented adverse matrix remodeling, increased angiogenesis, and preserved heart function. These results suggested that the injectable cardiac tissue engineering based on chitosan hydrogel and BADSCs is a useful strategy for myocardium regeneration. PMID:24508080

  11. Matrix Metalloproteinase-10 Promotes Kras-Mediated Bronchio-Alveolar Stem Cell Expansion and Lung Cancer Formation

    PubMed Central

    Regala, Roderick P.; Justilien, Verline; Walsh, Michael P.; Weems, Capella; Khoor, Andras; Murray, Nicole R.; Fields, Alan P.

    2011-01-01

    Matrix metalloproteinase 10 (MMP-10; stromelysin 2) is a member of a large family of structurally related matrix metalloproteinases, many of which have been implicated in tumor progression, invasion and metastasis. We recently identified Mmp10 as a gene that is highly induced in tumor-initiating lung bronchioalveolar stem cells (BASCs) upon activation of oncogenic Kras in a mouse model of lung adenocarcinoma. However, the potential role of Mmp10 in lung tumorigenesis has not been addressed. Here, we demonstrate that Mmp10 is overexpressed in lung tumors induced by either the smoke carcinogen urethane or oncogenic Kras. In addition, we report a significant reduction in lung tumor number and size after urethane exposure or genetic activation of oncogenic Kras in Mmp10 null (Mmp10−/−) mice. This inhibitory effect is reflected in a defect in the ability of Mmp10-deficient BASCs to expand and undergo transformation in response to urethane or oncogenic Kras in vivo and in vitro, demonstrating a role for Mmp10 in the tumor-initiating activity of Kras-transformed lung stem cells. To determine the potential relevance of MMP10 in human cancer we analyzed Mmp10 expression in publicly-available gene expression profiles of human cancers. Our analysis reveals that MMP10 is highly overexpressed in human lung tumors. Gene set enhancement analysis (GSEA) demonstrates that elevated MMP10 expression correlates with both cancer stem cell and tumor metastasis genomic signatures in human lung cancer. Finally, Mmp10 is elevated in many human tumor types suggesting a widespread role for Mmp10 in human malignancy. We conclude that Mmp10 plays an important role in lung tumor initiation via maintenance of a highly tumorigenic, cancer-initiating, stem-like cell population, and that Mmp10 expression is associated with stem-like, highly metastatic genotypes in human lung cancers. These results indicate that Mmp10 may represent a novel therapeutic approach to target lung cancer stem cells

  12. Brain tumor stem cells.

    PubMed

    Palm, Thomas; Schwamborn, Jens C

    2010-06-01

    Since the end of the 'no-new-neuron' theory, emerging evidence from multiple studies has supported the existence of stem cells in neurogenic areas of the adult brain. Along with this discovery, neural stem cells became candidate cells being at the origin of brain tumors. In fact, it has been demonstrated that molecular mechanisms controlling self-renewal and differentiation are shared between brain tumor stem cells and neural stem cells and that corruption of genes implicated in these pathways can direct tumor growth. In this regard, future anticancer approaches could be inspired by uncovering such redundancies and setting up treatments leading to exhaustion of the cancer stem cell pool. However, deleterious effects on (normal) neural stem cells should be minimized. Such therapeutic models underline the importance to study the cellular mechanisms implicated in fate decisions of neural stem cells and the oncogenic derivation of adult brain cells. In this review, we discuss the putative origins of brain tumor stem cells and their possible implications on future therapies. PMID:20370314

  13. The leukemic stem cell

    PubMed Central

    Jordan, Craig T.

    2007-01-01

    Malignant stem cells have recently been described as the source of several types of human cancer. These unique cell types are typically rare and possess properties that are distinct from most other tumor cells. The properties of leukemic stem cells indicate that current chemotherapy drugs will not be effective. The use of current cytotoxic agents is not effective in leukemia because the agents target both the leukemic and normal stem cell populations. Consequently, new strategies are required that specifically and preferentially target the malignant stem cell population, while sparing normal stem cells. Several well known agents are lethal for the leukemic stem cell in preclinical testing. They include parthenolide, commonly known as feverfew, and TDZD-8. They have undergone various levels of preclinical development, but have not been used in patients as yet in the cancer setting. These drugs and combinations of existing therapies that target the leukemic stem cell population may provide a cure in this disease. This article summarizes recent findings in the leukemic stem cell field and discusses new directions for therapy. PMID:17336250

  14. Stem Cell Separation Technologies

    PubMed Central

    Zhu, Beili; Murthy, Shashi K.

    2012-01-01

    Stem cell therapy and translational stem cell research require large-scale supply of stem cells at high purity and viability, thus leading to the development of stem cell separation technologies. This review covers key technologies being applied to stem cell separation, and also highlights exciting new approaches in this field. First, we will cover conventional separation methods that are commercially available and have been widely adapted. These methods include Fluorescence-activated cell sorting (FACS), Magnet-activated cell sorting (MACS), pre-plating, conditioned expansion media, density gradient centrifugation, field flow fractionation (FFF), and dielectrophoresis (DEP). Next, we will introduce emerging novel methods that are currently under development. These methods include improved aqueous two-phase system, systematic evolution of ligands by exponential enrichment (SELEX), and various types of microfluidic platforms. Finally, we will discuss the challenges and directions towards future breakthroughs for stem cell isolation. Advancing stem cell separation techniques will be essential for clinical and research applications of stem cells. PMID:23505616

  15. Wnt/β-catenin and LIF–Stat3 signaling pathways converge on Sp5 to promote mouse embryonic stem cell self-renewal

    PubMed Central

    Ye, Shoudong; Zhang, Dongming; Cheng, Fei; Wilson, Daniel; Mackay, Jeffrey; He, Kan; Ban, Qian; Lv, Feng; Huang, Saifei; Liu, Dahai; Ying, Qi-Long

    2016-01-01

    ABSTRACT Activation of leukemia inhibitor factor (LIF)–Stat3 or Wnt/β-catenin signaling promotes mouse embryonic stem cell (mESC) self-renewal. A myriad of downstream targets have been identified in the individual signal pathways, but their common targets remain largely elusive. In this study, we found that the LIF–Stat3 and Wnt/β-catenin signaling pathways converge on Sp5 to promote mESC self-renewal. Forced Sp5 expression can reproduce partial effects of Wnt/β-catenin signaling but mimics most features of LIF–Stat3 signaling to maintain undifferentiated mESCs. Moreover, Sp5 is able to convert mouse epiblast stem cells into a naïve pluripotent state. Thus, Sp5 is an important component of the regulatory network governing mESC naïve pluripotency. PMID:26598557

  16. Enhancement of adhesion and promotion of osteogenic differentiation of human adipose stem cells by poled electroactive poly(vinylidene fluoride).

    PubMed

    Pärssinen, Jenita; Hammarén, Henrik; Rahikainen, Rolle; Sencadas, Vitor; Ribeiro, Clarisse; Vanhatupa, Sari; Miettinen, Susanna; Lanceros-Méndez, Senentxu; Hytönen, Vesa P

    2015-03-01

    Poly(vinylidene fluoride) (PVDF) is a biocompatible material with excellent electroactive properties. Nonelectroactive α-PVDF and electroactive β-PVDF were used to investigate the substrate polarization and polarity influence on the focal adhesion (FA) size and number as well as on human adipose stem cells (hASCs) differentiation. hASCs were cultured on different PVDF surfaces adsorbed with fibronectin and FA size and number, total adhesion area, cell size, cell aspect ratio and FA density were estimated using cells expressing vinculin fused to enhanced green fluorescent protein. Osteogenic differentiation was also determined using a quantitative alkaline phosphatase assay. The surface charge of the poled PVDF films (positive or negative) influenced the hydrophobicity of the samples, leading to variations in the conformation of adsorbed extracellular matrix proteins, which ultimately modulated the stem cell adhesion on the films and induced their osteogenic differentiation. PMID:24838756

  17. Intranasally administered mesenchymal stem cells promote a regenerative niche for repair of neonatal ischemic brain injury.

    PubMed

    Donega, Vanessa; Nijboer, Cora H; van Tilborg, Geralda; Dijkhuizen, Rick M; Kavelaars, Annemieke; Heijnen, Cobi J

    2014-11-01

    Previous work from our group has shown that intranasal MSC-treatment decreases lesion volume and improves motor and cognitive behavior after hypoxic-ischemic (HI) brain damage in neonatal mice. Our aim was to determine the kinetics of MSC migration after intranasal administration, and the early effects of MSCs on neurogenic processes and gliosis at the lesion site. HI brain injury was induced in 9-day-old mice and MSCs were administered intranasally at 10days post-HI. The kinetics of MSC migration were investigated by immunofluorescence and MRI analysis. BDNF and NGF gene expression was determined by qPCR analysis following MSC co-culture with HI brain extract. Nestin, Doublecortin, NeuN, GFAP, Iba-1 and M1/M2 phenotypic expression was assessed over time. MRI and immunohistochemistry analyses showed that MSCs reach the lesion site already within 2h after intranasal administration. At 12h after administration the number of MSCs at the lesion site peaks and decreases significantly at 72h. The number of DCX(+) cells increased 1 to 3days after MSC administration in the SVZ. At the lesion, GFAP(+)/nestin(+) and DCX(+) expression increased 3 to 5days after MSC-treatment. The number of NeuN(+) cells increased within 5days, leading to a dramatic regeneration of the somatosensory cortex and hippocampus at 18days after intranasal MSC administration. Interestingly, MSCs expressed significantly more BDNF gene when exposed to HI brain extract in vitro. Furthermore, MSC-treatment resulted in the resolution of the glial scar surrounding the lesion, represented by a decrease in reactive astrocytes and microglia and polarization of microglia towards the M2 phenotype. In view of the current lack of therapeutic strategies, we propose that intranasal MSC administration is a powerful therapeutic option through its functional repair of the lesion represented by regeneration of the cortical and hippocampal structure and decrease of gliosis. PMID:24945601

  18. Methods for Stem Cell Production and Therapy

    NASA Technical Reports Server (NTRS)

    Claudio, Pier Paolo (Inventor); Valluri, Jagan V. (Inventor)

    2015-01-01

    The present invention relates to methods for rapidly expanding a stem cell population with or without culture supplements in simulated microgravity conditions. The present invention relates to methods for rapidly increasing the life span of stem cell populations without culture supplements in simulated microgravity conditions. The present invention also relates to methods for increasing the sensitivity of cancer stem cells to chemotherapeutic agents by culturing the cancer stem cells under microgravity conditions and in the presence of omega-3 fatty acids. The methods of the present invention can also be used to proliferate cancer cells by culturing them in the presence of omega-3 fatty acids. The present invention also relates to methods for testing the sensitivity of cancer cells and cancer stem cells to chemotherapeutic agents by culturing the cancer cells and cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce tissue for use in transplantation by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors to promote differentiation of cancer stem cells under microgravity conditions.

  19. Stem cells in dermatology*

    PubMed Central

    Ogliari, Karolyn Sassi; Marinowic, Daniel; Brum, Dario Eduardo; Loth, Fabrizio

    2014-01-01

    Preclinical and clinical research have shown that stem cell therapy could be a promising therapeutic option for many diseases in which current medical treatments do not achieve satisfying results or cure. This article describes stem cells sources and their therapeutic applications in dermatology today. PMID:24770506

  20. Stem Cell Transplants (For Teens)

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Stem Cell Transplants KidsHealth > For Teens > Stem Cell Transplants Print ... Does it Take to Recover? Coping What Are Stem Cells? As you probably remember from biology class, every ...

  1. Promoting effect of small molecules in cardiomyogenic and neurogenic differentiation of rat bone marrow-derived mesenchymal stem cells

    PubMed Central

    Khanabdali, Ramin; Saadat, Anbarieh; Fazilah, Maizatul; Bazli, Khairul Fidaa’ Khairul; Qazi, Rida-e-Maria; Khalid, Ramla Sana; Hasan Adli, Durriyyah Sharifah; Moghadamtousi, Soheil Zorofchian; Naeem, Nadia; Khan, Irfan; Salim, Asmat; Shamsuddin, ShamsulAzlin Ahmad; Mohan, Gokula

    2016-01-01

    Small molecules, growth factors, and cytokines have been used to induce differentiation of stem cells into different lineages. Similarly, demethylating agents can trigger differentiation in adult stem cells. Here, we investigated the in vitro differentiation of rat bone marrow mesenchymal stem cells (MSCs) into cardiomyocytes by a demethylating agent, zebularine, as well as neuronal-like cells by β-mercaptoethanol in a growth factor or cytokines-free media. Isolated bone marrow-derived MSCs cultured in Dulbecco’s Modified Eagle’s Medium exhibited a fibroblast-like morphology. These cells expressed positive markers for CD29, CD44, and CD117 and were negative for CD34 and CD45. After treatment with 1 μM zebularine for 24 hours, the MSCs formed myotube-like structures after 10 days in culture. Expression of cardiac-specific genes showed that treated MSCs expressed significantly higher levels of cardiac troponin-T, Nkx2.5, and GATA-4 compared with untreated cells. Immunocytochemical analysis showed that differentiated cells also expressed cardiac proteins, GATA-4, Nkx 2.5, and cardiac troponin-T. For neuronal differentiation, MSCs were treated with 1 and 10 mM β-mercaptoethanol overnight for 3 hours in complete and serum-free Dulbecco’s Modified Eagle’s Medium, respectively. Following overnight treatment, neuron-like cells with axonal and dendritic-like projections originating from the cell body toward the neighboring cells were observed in the culture. The mRNA expression of neuronal-specific markers, Map2, Nefl, Tau, and Nestin, was significantly higher, indicating that the treated cells differentiated into neuronal-like cells. Immunostaining showed that differentiated cells were positive for the neuronal markers Flk, Nef, Nestin, and β-tubulin. PMID:26766903

  2. Increased SCF/c-kit by hypoxia promotes autophagy of human placental chorionic plate-derived mesenchymal stem cells via regulating the phosphorylation of mTOR.

    PubMed

    Lee, Youjin; Jung, Jieun; Cho, Kyung Jin; Lee, Seoung-Kwan; Park, Jong-Wan; Oh, Il-Hoan; Kim, Gi Jin

    2013-01-01

    Hypoxia triggers physiological and pathological cellular processes, including proliferation, differentiation, and death, in several cell types. Mesenchymal stem cells (MSCs) derived from various tissues have self-renewal activity and can differentiate towards multiple lineages. Recently, it has been reported that hypoxic conditions tip the balance between survival and death by hypoxia-induced autophagy, although the underlying mechanism is not clear. The objectives of this study are to compare the effect of hypoxia on the self-renewal of bone marrow-derived mesenchymal stem cells (BM-MSCs) and placental chorionic plate-derived mesenchymal stem cells (CP-MSCs) and to investigate the regulatory mechanisms of self-renewal in each MSC type during hypoxia. The expression of self-renewal markers (e.g., Oct4, Nanog, Sox2) was assessed in both cell lines. PI3K and stem cell factor (SCF) expression gradually increased in CP-MSCs but were markedly downregulated in BM-MSCs by hypoxia. The phosphorylation of ERK and mTOR was augmented by hypoxia in CP-MSCs compared to control. Also, the expression of LC3 II, a component of the autophagosome and the hoof-shaped autophagosome was detected more rapidly in CP-MSCs than in BM-MSCs under hypoxia. Hypoxia induced the expression of SCF in CP-MSCs and increased SCF/c-kit pathway promotes the self-renewal activities of CP-MSCs via an autocrine/paracrine mechanism that balances cell survival and cell death events by autophagy. These activities occur to a greater extent in CP-MSCs than in BM-MSCs through regulating the phosphorylation of mTOR. These findings will provide useful guidelines for better understanding the function of SCF/c-kit in the self-renewal and autophagy-regulated mechanisms that promote of MSC survival. PMID:22833529

  3. Human haematopoietic stem cells express Oct4 pseudogenes and lack the ability to initiate Oct4 promoter-driven gene expression.

    PubMed

    Redshaw, Zoe; Strain, Alastair J

    2010-01-01

    The transcription factor Oct4 is well defined as a key regulator of embryonic stem (ES) cell pluripotency. In recent years, the role of Oct4 has purportedly extended to the self renewal and maintenance of multipotency in adult stem cell (ASC) populations. This profile has arisen mainly from reports utilising reverse transcription-polymerase chain reaction (RT-PCR) based methodologies and has since come under scrutiny following the discovery that many developmental genes have multiple pseudogenes associated with them. Six known pseudogenes exist for Oct4, all of which exhibit very high sequence homology (three >97%), and for this reason the generation of artefacts may have contributed to false identification of Oct4 in somatic cell populations. While ASC lack a molecular blueprint of transcription factors proposed to be involved with 'stemness' as described for ES cells, it is not unreasonable to assume that similar gene patterns may exist. The focus of this work was to corroborate reports that Oct4 is involved in the regulation of ASC self-renewal and differentiation, using a combination of methodologies to rule out pseudogene interference. Haematopoietic stem cells (HSC) derived from human umbilical cord blood (UCB) and various differentiated cell lines underwent RT-PCR, product sequencing and transfection studies using an Oct4 promoter-driven reporter. In summary, only the positive control expressed Oct4, with all other cell types expressing a variety of Oct4 pseudogenes. Somatic cells were incapable of utilising an exogenous Oct4 promoter construct, leading to the conclusion that Oct4 does not appear involved in the multipotency of human HSC from UCB. PMID:20356403

  4. Promoting the selection and maintenance of fetal liver stem/progenitor cell colonies by layer-by-layer polypeptide tethered supported lipid bilayer.

    PubMed

    Lee, I-Chi; Liu, Yung-Chiang; Tsai, Hsuan-Ang; Shen, Chia-Ning; Chang, Ying-Chih

    2014-12-10

    In this study, we designed and constructed a series of layer-by-layer polypeptide adsorbed supported lipid bilayer (SLB) films as a novel and label-free platform for the isolation and maintenance of rare populated stem cells. In particular, four alternative layers of anionic poly-l-glutamic acid and cationic poly-l-lysine were sequentially deposited on an anionic SLB. We found that the fetal liver stem/progenitor cells from the primary culture were selected and formed colonies on all layer-by-layer polypeptide adsorbed SLB surfaces, regardless of the number of alternative layers and the net charges on those layers. Interestingly, these isolated stem/progenitor cells formed colonies which were maintained for an 8 day observation period. Quartz crystal microbalance with dissipation measurements showed that all SLB-polypeptide films were protein resistant with serum levels significantly lower than those on the polypeptide multilayer films without an underlying SLB. We suggest the fluidic SLB promotes selective binding while minimizing the cell-surface interaction due to its nonfouling nature, thus limiting stem cell colonies from spreading. PMID:25243588

  5. Hematopoietic stem cell transplantation

    PubMed Central

    Hatzimichael, Eleftheria; Tuthill, Mark

    2010-01-01

    More than 25,000 hematopoietic stem cell transplantations (HSCTs) are performed each year for the treatment of lymphoma, leukemia, immune-deficiency illnesses, congenital metabolic defects, hemoglobinopathies, and myelodysplastic and myeloproliferative syndromes. Before transplantation, patients receive intensive myeloablative chemoradiotherapy followed by stem cell “rescue.” Autologous HSCT is performed using the patient’s own hematopoietic stem cells, which are harvested before transplantation and reinfused after myeloablation. Allogeneic HSCT uses human leukocyte antigen (HLA)-matched stem cells derived from a donor. Survival after allogeneic transplantation depends on donor–recipient matching, the graft-versus-host response, and the development of a graft versus leukemia effect. This article reviews the biology of stem cells, clinical efficacy of HSCT, transplantation procedures, and potential complications. PMID:24198516

  6. Promotion of chondrogenesis of marrow stromal stem cells by TGF-β3 fusion protein in vivo. [corrected].

    PubMed

    Wu, Wei; Dan, Yang; Yang, Shu-hua; Yang, Cao; Shao, Zeng-wu; Xu, Wei-hua; Li, Jin; Liu, Xian-zhe; Zheng, Dong

    2013-10-01

    The purpose of this study was to investigate the repair of the osteoarthritis(OA)-induced cartilage injury by transfecting the new TGF-β3 fusion protein (LAP-MMP-mTGF-β3) with targeted therapy function into the bone marrow-derived mesenchymal stem cells (MSCs) in rats. The recombinant of pIRES-EGFP-MMP was constructed by combination of DNA encoding MMP enzyme cutting site and eukaryotic expression vector pIRES-EGFP. LAP and mTGF-β3 fragments were obtained from rat embryos by RT-PCR and inserted into the upstream and downstream of MMP from pIRES-EGFP-MMP respectively, so as to construct the recombinant plasmid of pIRES-EGFP-LAP-MMP-mTGF-β3. pIRES-EGFP-LAP-MMP-mTGF-β3 was transfected into rat MSCs. The genetically modified MSCs were cultured in medium with MMP-1 or not. The transfected MSCs were transplanted in the rat OA models. The OA animal models were surgically induced by anterior cruciate ligament transaction (ACLT). The pathological changes were observed under a microscope by HE staining, Alcian blue, Safranin-fast Green and graded by Mankin's scale. pIRES-EGFP-LAP-MMP-mTGF-β3 was successfully constructed by means of enzyme cutting and sequencing, and the mTGF-β3 fusion protein (39 kD) was certified by Western blotting. Those genetically modified MSCs could differentiate into chondrocytes induced by MMP and secrete the relevant-matrix. The transfected MSCs could promote chondrogenesis and matrix production in rat OA models in vivo. It was concluded that a new fusion protein LAP-MMP-mTGF-β3 was constructed successfully by gene engineering, and could be used to repair the OA-induced cartilage injury. PMID:24142722

  7. Mesenchymal stem cells.

    PubMed

    Ding, Dah-Ching; Shyu, Woei-Cherng; Lin, Shinn-Zong

    2011-01-01

    Stem cells have two features: the ability to differentiate along different lineages and the ability of self-renewal. Two major types of stem cells have been described, namely, embryonic stem cells and adult stem cells. Embryonic stem cells (ESC) are obtained from the inner cell mass of the blastocyst and are associated with tumorigenesis, and the use of human ESCs involves ethical and legal considerations. The use of adult mesenchymal stem cells is less problematic with regard to these issues. Mesenchymal stem cells (MSCs) are stromal cells that have the ability to self-renew and also exhibit multilineage differentiation. MSCs can be isolated from a variety of tissues, such as umbilical cord, endometrial polyps, menses blood, bone marrow, adipose tissue, etc. This is because the ease of harvest and quantity obtained make these sources most practical for experimental and possible clinical applications. Recently, MSCs have been found in new sources, such as menstrual blood and endometrium. There are likely more sources of MSCs waiting to be discovered, and MSCs may be a good candidate for future experimental or clinical applications. One of the major challenges is to elucidate the mechanisms of differentiation, mobilization, and homing of MSCs, which are highly complex. The multipotent properties of MSCs make them an attractive choice for possible development of clinical applications. Future studies should explore the role of MSCs in differentiation, transplantation, and immune response in various diseases. PMID:21396235

  8. Functionalizing Ascl1 with Novel Intracellular Protein Delivery Technology for Promoting Neuronal Differentiation of Human Induced Pluripotent Stem Cells.

    PubMed

    Robinson, Meghan; Chapani, Parv; Styan, Tara; Vaidyanathan, Ranjani; Willerth, Stephanie Michelle

    2016-08-01

    Pluripotent stem cells can become any cell type found in the body. Accordingly, one of the major challenges when working with pluripotent stem cells is producing a highly homogenous population of differentiated cells, which can then be used for downstream applications such as cell therapies or drug screening. The transcription factor Ascl1 plays a key role in neural development and previous work has shown that Ascl1 overexpression using viral vectors can reprogram fibroblasts directly into neurons. Here we report on how a recombinant version of the Ascl1 protein functionalized with intracellular protein delivery technology (Ascl1-IPTD) can be used to rapidly differentiate human induced pluripotent stem cells (hiPSCs) into neurons. We first evaluated a range of Ascl1-IPTD concentrations to determine the most effective amount for generating neurons from hiPSCs cultured in serum free media. Next, we looked at the frequency of Ascl1-IPTD supplementation in the media on differentiation and found that one time supplementation is sufficient enough to trigger the neural differentiation process. Ascl1-IPTD was efficiently taken up by the hiPSCs and enabled rapid differentiation into TUJ1-positive and NeuN-positive populations with neuronal morphology after 8 days. After 12 days of culture, hiPSC-derived neurons produced by Ascl1-IPTD treatment exhibited greater neurite length and higher numbers of branch points compared to neurons derived using a standard neural progenitor differentiation protocol. This work validates Ascl1-IPTD as a powerful tool for engineering neural tissue from pluripotent stem cells. PMID:27138845

  9. Symposium Promotes Technological Literacy through STEM

    ERIC Educational Resources Information Center

    Havice, Bill; Marshall, Jerry

    2009-01-01

    This article describes a symposium which promotes technological literacy through science, technology, engineering, and mathematics (STEM). The three-day symposium titled, "The Anderson, Oconee, Pickens Symposium on Teaching and Learning STEM Standards for the 21st Century," was held August 4-6, 2008 at the Tri-County Technical College (TCTC)…

  10. Systematic selection of small molecules to promote differentiation of embryonic stem cells and experimental validation for generating cardiomyocytes.

    PubMed

    KalantarMotamedi, Y; Peymani, M; Baharvand, H; Nasr-Esfahani, M H; Bender, A

    2016-01-01

    Small molecules are being increasingly used for inducing the targeted differentiation of stem cells to different cell types. However, until now no systematic method for selecting suitable small molecules for this purpose has been presented. In this work, we propose an integrated and general bioinformatics- and cheminformatics-based approach for selecting small molecules which direct cellular differentiation in the desired way. The approach was successfully experimentally validated for differentiating stem cells into cardiomyocytes. All predicted compounds enhanced expression of cardiac progenitor (Gata4, Nkx2-5 and Mef2c) and mature cardiac markers (Actc1, myh6) significantly during and post-cardiac progenitor formation. The best-performing compound, Famotidine, increased the percentage of Myh6-positive cells from 33 to 56%, and enhanced the expression of Nkx2.5 and Tnnt2 cardiac progenitor and cardiac markers in protein level. The approach employed in the study is applicable to all other stem cell differentiation settings where gene expression data are available. PMID:27551501

  11. Systematic selection of small molecules to promote differentiation of embryonic stem cells and experimental validation for generating cardiomyocytes

    PubMed Central

    KalantarMotamedi, Y; Peymani, M; Baharvand, H; Nasr-Esfahani, M H; Bender, A

    2016-01-01

    Small molecules are being increasingly used for inducing the targeted differentiation of stem cells to different cell types. However, until now no systematic method for selecting suitable small molecules for this purpose has been presented. In this work, we propose an integrated and general bioinformatics- and cheminformatics-based approach for selecting small molecules which direct cellular differentiation in the desired way. The approach was successfully experimentally validated for differentiating stem cells into cardiomyocytes. All predicted compounds enhanced expression of cardiac progenitor (Gata4, Nkx2-5 and Mef2c) and mature cardiac markers (Actc1, myh6) significantly during and post-cardiac progenitor formation. The best-performing compound, Famotidine, increased the percentage of Myh6-positive cells from 33 to 56%, and enhanced the expression of Nkx2.5 and Tnnt2 cardiac progenitor and cardiac markers in protein level. The approach employed in the study is applicable to all other stem cell differentiation settings where gene expression data are available. PMID:27551501

  12. Autophagy in stem cells

    PubMed Central

    Guan, Jun-Lin; Simon, Anna Katharina; Prescott, Mark; Menendez, Javier A.; Liu, Fei; Wang, Fen; Wang, Chenran; Wolvetang, Ernst; Vazquez-Martin, Alejandro; Zhang, Jue

    2013-01-01

    Autophagy is a highly conserved cellular process by which cytoplasmic components are sequestered in autophagosomes and delivered to lysosomes for degradation. As a major intracellular degradation and recycling pathway, autophagy is crucial for maintaining cellular homeostasis as well as remodeling during normal development, and dysfunctions in autophagy have been associated with a variety of pathologies including cancer, inflammatory bowel disease and neurodegenerative disease. Stem cells are unique in their ability to self-renew and differentiate into various cells in the body, which are important in development, tissue renewal and a range of disease processes. Therefore, it is predicted that autophagy would be crucial for the quality control mechanisms and maintenance of cellular homeostasis in various stem cells given their relatively long life in the organisms. In contrast to the extensive body of knowledge available for somatic cells, the role of autophagy in the maintenance and function of stem cells is only beginning to be revealed as a result of recent studies. Here we provide a comprehensive review of the current understanding of the mechanisms and regulation of autophagy in embryonic stem cells, several tissue stem cells (particularly hematopoietic stem cells), as well as a number of cancer stem cells. We discuss how recent studies of different knockout mice models have defined the roles of various autophagy genes and related pathways in the regulation of the maintenance, expansion and differentiation of various stem cells. We also highlight the many unanswered questions that will help to drive further research at the intersection of autophagy and stem cell biology in the near future. PMID:23486312

  13. Insulin-like Growth Factor-II (IGF-II) and IGF-II Analogs with Enhanced Insulin Receptor-a Binding Affinity Promote Neural Stem Cell Expansion*

    PubMed Central

    Ziegler, Amber N.; Chidambaram, Shravanthi; Forbes, Briony E.; Wood, Teresa L.; Levison, Steven W.

    2014-01-01

    The objective of this study was to employ genetically engineered IGF-II analogs to establish which receptor(s) mediate the stemness promoting actions of IGF-II on mouse subventricular zone neural precursors. Neural precursors from the subventricular zone were propagated in vitro in culture medium supplemented with IGF-II analogs. Cell growth and identity were analyzed using sphere generation and further analyzed by flow cytometry. F19A, an analog of IGF-II that does not bind the IGF-2R, stimulated an increase in the proportion of neural stem cells (NSCs) while decreasing the proportion of the later stage progenitors at a lower concentration than IGF-II. V43M, which binds to the IGF-2R with high affinity but which has low binding affinity to the IGF-1R and to the A isoform of the insulin receptor (IR-A) failed to promote NSC growth. The positive effects of F19A on NSC growth were unaltered by the addition of a functional blocking antibody to the IGF-1R. Altogether, these data lead to the conclusion that IGF-II promotes stemness of NSCs via the IR-A and not through activation of either the IGF-1R or the IGF-2R. PMID:24398690

  14. Pigment Epithelium-Derived Factor (PEDF) Expression Induced by EGFRvIII Promotes Self-renewal and Tumor Progression of Glioma Stem Cells.

    PubMed

    Yin, Jinlong; Park, Gunwoo; Kim, Tae Hoon; Hong, Jun Hee; Kim, Youn-Jae; Jin, Xiong; Kang, Sangjo; Jung, Ji-Eun; Kim, Jeong-Yub; Yun, Hyeongsun; Lee, Jeong Eun; Kim, Minkyung; Chung, Junho; Kim, Hyunggee; Nakano, Ichiro; Gwak, Ho-Shin; Yoo, Heon; Yoo, Byong Chul; Kim, Jong Heon; Hur, Eun-Mi; Lee, Jeongwu; Lee, Seung-Hoon; Park, Myung-Jin; Park, Jong Bae

    2015-05-01

    Epidermal growth factor receptor variant III (EGFRvIII) has been associated with glioma stemness, but the direct molecular mechanism linking the two is largely unknown. Here, we show that EGFRvIII induces the expression and secretion of pigment epithelium-derived factor (PEDF) via activation of signal transducer and activator of transcription 3 (STAT3), thereby promoting self-renewal and tumor progression of glioma stem cells (GSCs). Mechanistically, PEDF sustained GSC self-renewal by Notch1 cleavage, and the generated intracellular domain of Notch1 (NICD) induced the expression of Sox2 through interaction with its promoter region. Furthermore, a subpopulation with high levels of PEDF was capable of infiltration along corpus callosum. Inhibition of PEDF diminished GSC self-renewal and increased survival of orthotopic tumor-bearing mice. Together, these data indicate the novel role of PEDF as a key regulator of GSC and suggest clinical implications. PMID:25992628

  15. Human iPSC-Derived Neural Crest Stem Cells Promote Tendon Repair in a Rat Patellar Tendon Window Defect Model

    PubMed Central

    Xu, Wei; Wang, Yequan; Liu, Erfu; Sun, Yanjun; Luo, Ziwei; Xu, Zhiling; Liu, Wanqian; Zhong, Li; Lv, Yonggang; Wang, Aijun; Tang, Zhenyu; Li, Song

    2013-01-01

    Induced pluripotent stem cells (iPSCs) hold great potential for cell therapy and tissue engineering. Neural crest stem cells (NCSCs) are multipotent that are capable of differentiating into mesenchymal lineages. In this study, we investigated whether iPSC-derived NCSCs (iPSC-NCSCs) have potential for tendon repair. Human iPSC-NCSCs were suspended in fibrin gel and transplanted into a rat patellar tendon window defect. At 4 weeks post-transplantation, macroscopical observation showed that the repair of iPSC-NCSC-treated tendons was superior to that of non-iPSC-NCSC-treated tendons. Histological and mechanical examinations revealed that iPSC-NCSCs treatment significantly enhanced tendon healing as indicated by the improvement in matrix synthesis and mechanical properties. Furthermore, transplanted iPSC-NCSCs produced fetal tendon-related matrix proteins, stem cell recruitment factors, and tenogenic differentiation factors, and accelerated the host endogenous repair process. This study demonstrates a potential strategy of employing iPSC-derived NCSCs for tendon tissue engineering. PMID:23815150

  16. Micropatterning Extracellular Matrix Proteins on Electrospun Fibrous Substrate Promote Human Mesenchymal Stem Cell Differentiation Toward Neurogenic Lineage.

    PubMed

    Li, Huaqiong; Wen, Feng; Chen, Huizhi; Pal, Mintu; Lai, Yuekun; Zhao, Allan Zijian; Tan, Lay Poh

    2016-01-13

    In this study, hybrid micropatterned grafts constructed via a combination of microcontact printing and electrospinning techniques process were utilized to investigate the influencing of patterning directions on human mesenchymal stem cells (hMSCs) differentiation to desired phenotypes. We found that the stem cells could align and elongate along the direction of the micropattern, where they randomly distributed on nonmicropatterned surfaces. Concomitant with patterning effect of component on stem cell alignment, a commensurate increase on the expression of neural lineage commitment markers, such as microtubule associated protein 2 (MAP2), Nestin, NeuroD1, and Class III β-Tubulin, were revealed from mRNA expression by quantitative Real Time PCR (qRT-PCR) and MAP2 expression by immunostaining. In addition, the effect of electrospun fiber orientation on cell behaviors was further examined. An angle of 45° between the direction of micropatterning and orientation of aligned fibers was verified to greatly prompt the outgrowth of filopodia and neurogenesis of hMSCs. This study demonstrates that the significance of hybrid components and electrospun fiber alignment in modulating cellular behavior and neurogenic lineage commitment of hMSCs, suggesting promising application of porous scaffolds with smart component and topography engineering in clinical regenerative medicine. PMID:26654444

  17. Dickkopf-1-promoted vasculogenic mimicry in non-small cell lung cancer is associated with EMT and development of a cancer stem-like cell phenotype.

    PubMed

    Yao, Lingli; Zhang, Danfang; Zhao, Xiulan; Sun, Baocun; Liu, Yanrong; Gu, Qiang; Zhang, Yanhui; Zhao, Xueming; Che, Na; Zheng, Yanjun; Liu, Fang; Wang, Yong; Meng, Jie

    2016-09-01

    To characterize the contributions of Dickkopf-1 (DKK1) towards the induction of vasculogenic mimicry (VM) in non-small cell lung cancer (NSCLC), we evaluated cohorts of primary tumours, performed in vitro functional studies and generated xenograft mouse models. Vasculogenic mimicry was observed in 28 of 205 NSCLC tumours, while DKK1 was detected in 133 cases. Notably, DKK1 was positively associated with VM. Statistical analysis showed that VM and DKK1 were both related to aggressive clinical course and thus were indicators of a poor prognosis. Moreover, expression of epithelial-mesenchymal transition (EMT)-related proteins (vimentin, Slug, and Twist), cancer stem-like cell (CSC)-related proteins (nestin and CD44), VM-related proteins (MMP2, MMP9, and vascular endothelial-cadherin), and β-catenin-nu were all elevated in VM-positive and DKK1-positive tumours, whereas the epithelial marker (E-cadherin) was reduced in the VM-positive and DKK1-positive groups. Non-small cell lung cancer cell lines with overexpressed or silenced DKK1 highlighted its role in the restoration of mesenchymal phenotypes and development of CSC characteristics. Moreover, DKK1 significantly promotes NSCLC tumour cells to migrate, invade and proliferate. In vivo animal studies demonstrated that DKK1 enhances the growth of transplanted human tumours cells, as well as increased VM formation, mesenthymal phenotypes and CSC properties. Our results suggest that DKK1 can promote VM formation via induction of the expression of EMT and CSC-related proteins. As such, we feel that DKK1 may represent a novel target of NSCLC therapy. PMID:27240974

  18. Epithelial stem cells.

    PubMed

    Draheim, Kyle M; Lyle, Stephen

    2011-01-01

    It is likely that adult epithelial stem cells will be useful in the treatment of diseases, such as ectodermal dysplasias, monilethrix, Netherton syndrome, Menkes disease, hereditary epidermolysis bullosa, and alopecias. Additionally, other skin problems such as burn wounds, chronic wounds, and ulcers will benefit from stem cell-related therapies. However, there are many questions that need to be answered before this goal can be realized. The most important of these questions is what regulates the adhesion of stem cells to the niche versus migration to the site of injury. We have started to identify the mechanisms involved in this decision-making process. PMID:21618097

  19. Constitutive expression of Wnt/β-catenin target genes promotes proliferation and invasion of liver cancer stem cells

    PubMed Central

    CHEN, WEI; ZHANG, YU-WEI; LI, YANG; ZHANG, JIAN-WEN; ZHANG, TONG; FU, BIN-SHENG; ZHANG, QI; JIANG, NAN

    2016-01-01

    Wnt/β-catenin is an important signaling pathways involved in the tumorgenesis, progression and maintenance of cancer stem cells (CSCs). In the present study, the role of Wnt/β-catenin signaling in CSC-mediated tumorigenesis and invasion in liver CSCs was investigated. A small population of cancer stem-like side population (SP) cells (3.6%) from liver cancer samples were identified. The cells were highly resistant to drug treatment due to the enhanced expression of drug efflux pumps, such as ABC subfamily G member 2, multidrug resistance protein 1 and ATP-binding cassette subfamily B member 5. Furthermore, using TOPflash and reverse transcription-quantitative polymerase chain reaction analysis, Wnt/β-catenin signaling and the transcriptional regulation of Wnt/β-catenin target genes including dickkopf Wnt signaling pathway inhibitor 1, axis inhibition protein 2 and cyclin D1 were observed to be markedly upregulated in liver cancer SP cells. As a consequence, SP cells possessed infinite cell proliferation potential and the ability to generating tumor spheres. In addition, upon reducing Wnt/β-catenin signaling, the rates of proliferation, tumor sphere formation and tumor invasion of SP cells were markedly reduced. Therefore, these data suggest that Wnt/β-catenin signaling is a potential therapeutic target to reduce CSC-mediated tumorigenicity and invasion in liver cancer. PMID:26956539

  20. Promotion of Survival and Differentiation of Neural Stem Cells with Fibrin and Growth Factor Cocktails after Severe Spinal Cord Injury

    PubMed Central

    Lu, Paul; Graham, Lori; Wang, Yaozhi; Wu, Di; Tuszynski, Mark

    2014-01-01

    Neural stem cells (NSCs) can self-renew and differentiate into neurons and glia. Transplanted NSCs can replace lost neurons and glia after spinal cord injury (SCI), and can form functional relays to re-connect spinal cord segments above and below a lesion. Previous studies grafting neural stem cells have been limited by incomplete graft survival within the spinal cord lesion cavity. Further, tracking of graft cell survival, differentiation, and process extension had not been optimized. Finally, in previous studies, cultured rat NSCs were typically reported to differentiate into glia when grafted to the injured spinal cord, rather than neurons, unless fate was driven to a specific cell type. To address these issues, we developed new methods to improve the survival, integration and differentiation of NSCs to sites of even severe SCI. NSCs were freshly isolated from embryonic day 14 spinal cord (E14) from a stable transgenic Fischer 344 rat line expressing green fluorescent protein (GFP) and were embedded into a fibrin matrix containing growth factors; this formulation aimed to retain grafted cells in the lesion cavity and support cell survival. NSCs in the fibrin/growth factor cocktail were implanted two weeks after thoracic level-3 (T3) complete spinal cord transections, thereby avoiding peak periods of inflammation. Resulting grafts completely filled the lesion cavity and differentiated into both neurons, which extended axons into the host spinal cord over remarkably long distances, and glia. Grafts of cultured human NSCs expressing GFP resulted in similar findings. Thus, methods are defined for improving neural stem cell grafting, survival and analysis of in vivo findings. PMID:25145787

  1. Gain of BDNF Function in Engrafted Neural Stem Cells Promotes the Therapeutic Potential for Alzheimer’s Disease

    PubMed Central

    Wu, Cheng-Chun; Lien, Cheng-Chang; Hou, Wen-Hsien; Chiang, Po-Min; Tsai, Kuen-Jer

    2016-01-01

    Stem cell-based therapy is a potential treatment for neurodegenerative diseases, but its application to Alzheimer’s disease (AD) remains limited. Brain-derived neurotrophic factor (BDNF) is critical in the pathogenesis and treatment of AD. Here, we present a novel therapeutic approach for AD treatment using BDNF-overexpressing neural stem cells (BDNF-NSCs). In vitro, BDNF overexpression was neuroprotective to beta-amyloid-treated NSCs. In vivo, engrafted BDNF-NSCs-derived neurons not only displayed the Ca2+-response fluctuations, exhibited electrophysiological properties of mature neurons and integrated into local brain circuits, but recovered the cognitive deficits. Furthermore, BDNF overexpression improved the engrafted cells’ viability, neuronal fate, neurite complexity, maturation of electrical property and the synaptic density. In contrast, knockdown of the BDNF in BDNF-NSCs diminished stem cell-based therapeutic efficacy. Together, our findings indicate BDNF overexpression improves the therapeutic potential of engrafted NSCs for AD via neurogenic effects and neuronal replacement, and further support the feasibility of NSC-based ex vivo gene therapy for AD. PMID:27264956

  2. SMOOTH MUSCLE STEM CELLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vascular smooth muscle cells (SMCs) originate from multiple types of progenitor cells. In the embryo, the most well-studied SMC progenitor is the cardiac neural crest stem cell. Smooth muscle differentiation in the neural crest lineage is controlled by a combination of cell intrinsic factors, includ...

  3. Structure-based discovery of NANOG variant with enhanced properties to promote self-renewal and reprogramming of pluripotent stem cells

    PubMed Central

    Hayashi, Yohei; Caboni, Laura; Das, Debanu; Yumoto, Fumiaki; Clayton, Thomas; Deller, Marc C.; Nguyen, Phuong; Farr, Carol L.; Chiu, Hsiu-Ju; Miller, Mitchell D.; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Tomoda, Kiichiro; Conklin, Bruce R.; Wilson, Ian A.; Yamanaka, Shinya; Fletterick, Robert J.

    2015-01-01

    NANOG (from Irish mythology Tír na nÓg) transcription factor plays a central role in maintaining pluripotency, cooperating with OCT4 (also known as POU5F1 or OCT3/4), SOX2, and other pluripotency factors. Although the physiological roles of the NANOG protein have been extensively explored, biochemical and biophysical properties in relation to its structural analysis are poorly understood. Here we determined the crystal structure of the human NANOG homeodomain (hNANOG HD) bound to an OCT4 promoter DNA, which revealed amino acid residues involved in DNA recognition that are likely to be functionally important. We generated a series of hNANOG HD alanine substitution mutants based on the protein–DNA interaction and evolutionary conservation and determined their biological activities. Some mutant proteins were less stable, resulting in loss or decreased affinity for DNA binding. Overexpression of the orthologous mouse NANOG (mNANOG) mutants failed to maintain self-renewal of mouse embryonic stem cells without leukemia inhibitory factor. These results suggest that these residues are critical for NANOG transcriptional activity. Interestingly, one mutant, hNANOG L122A, conversely enhanced protein stability and DNA-binding affinity. The mNANOG L122A, when overexpressed in mouse embryonic stem cells, maintained their expression of self-renewal markers even when retinoic acid was added to forcibly drive differentiation. When overexpressed in epiblast stem cells or human induced pluripotent stem cells, the L122A mutants enhanced reprogramming into ground-state pluripotency. These findings demonstrate that structural and biophysical information on key transcriptional factors provides insights into the manipulation of stem cell behaviors and a framework for rational protein engineering. PMID:25825768

  4. Structure-based discovery of NANOG variant with enhanced properties to promote self-renewal and reprogramming of pluripotent stem cells.

    PubMed

    Hayashi, Yohei; Caboni, Laura; Das, Debanu; Yumoto, Fumiaki; Clayton, Thomas; Deller, Marc C; Nguyen, Phuong; Farr, Carol L; Chiu, Hsiu-Ju; Miller, Mitchell D; Elsliger, Marc-André; Deacon, Ashley M; Godzik, Adam; Lesley, Scott A; Tomoda, Kiichiro; Conklin, Bruce R; Wilson, Ian A; Yamanaka, Shinya; Fletterick, Robert J

    2015-04-14

    NANOG (from Irish mythology Tír na nÓg) transcription factor plays a central role in maintaining pluripotency, cooperating with OCT4 (also known as POU5F1 or OCT3/4), SOX2, and other pluripotency factors. Although the physiological roles of the NANOG protein have been extensively explored, biochemical and biophysical properties in relation to its structural analysis are poorly understood. Here we determined the crystal structure of the human NANOG homeodomain (hNANOG HD) bound to an OCT4 promoter DNA, which revealed amino acid residues involved in DNA recognition that are likely to be functionally important. We generated a series of hNANOG HD alanine substitution mutants based on the protein-DNA interaction and evolutionary conservation and determined their biological activities. Some mutant proteins were less stable, resulting in loss or decreased affinity for DNA binding. Overexpression of the orthologous mouse NANOG (mNANOG) mutants failed to maintain self-renewal of mouse embryonic stem cells without leukemia inhibitory factor. These results suggest that these residues are critical for NANOG transcriptional activity. Interestingly, one mutant, hNANOG L122A, conversely enhanced protein stability and DNA-binding affinity. The mNANOG L122A, when overexpressed in mouse embryonic stem cells, maintained their expression of self-renewal markers even when retinoic acid was added to forcibly drive differentiation. When overexpressed in epiblast stem cells or human induced pluripotent stem cells, the L122A mutants enhanced reprogramming into ground-state pluripotency. These findings demonstrate that structural and biophysical information on key transcriptional factors provides insights into the manipulation of stem cell behaviors and a framework for rational protein engineering. PMID:25825768

  5. Structure-based discovery of NANOG variant with enhanced properties to promote self-renewal and reprogramming of pluripotent stem cells

    SciTech Connect

    Hayashi, Yohei; Caboni, Laura; Das, Debanu; Yumoto, Fumiaki; Clayton, Thomas; Deller, Marc C.; Nguyen, Phuong; Farr, Carol L.; Chiu, Hsiu -Ju; Miller, Mitchell D.; Elsliger, Marc -André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Tomoda, Kiichiro; Conklin, Bruce R.; Wilson, Ian A.; Yamanaka, Shinya; Fletterick, Robert J.

    2015-03-30

    NANOG (from Irish mythology Tír na nÓg) transcription factor plays a central role in maintaining pluripotency, cooperating with OCT4 (also known as POU5F1 or OCT3/4), SOX2, and other pluripotency factors. Although the physiological roles of the NANOG protein have been extensively explored, biochemical and biophysical properties in relation to its structural analysis are poorly understood. Here we determined the crystal structure of the human NANOG homeodomain (hNANOG HD) bound to an OCT4 promoter DNA, which revealed amino acid residues involved in DNA recognition that are likely to be functionally important. We generated a series of hNANOG HD alanine substitution mutants based on the protein–DNA interaction and evolutionary conservation and determined their biological activities. Some mutant proteins were less stable, resulting in loss or decreased affinity for DNA binding. Overexpression of the orthologous mouse NANOG (mNANOG) mutants failed to maintain self-renewal of mouse embryonic stem cells without leukemia inhibitory factor. These results suggest that these residues are critical for NANOG transcriptional activity. Interestingly, one mutant, hNANOG L122A, conversely enhanced protein stability and DNA-binding affinity. The mNANOG L122A, when overexpressed in mouse embryonic stem cells, maintained their expression of self-renewal markers even when retinoic acid was added to forcibly drive differentiation. When overexpressed in epiblast stem cells or human induced pluripotent stem cells, the L122A mutants enhanced reprogramming into ground-state pluripotency. These findings indicate that structural and biophysical information on key transcriptional factors provides insights into the manipulation of stem cell behaviors and a framework for rational protein engineering.

  6. Structure-based discovery of NANOG variant with enhanced properties to promote self-renewal and reprogramming of pluripotent stem cells

    DOE PAGESBeta

    Hayashi, Yohei; Caboni, Laura; Das, Debanu; Yumoto, Fumiaki; Clayton, Thomas; Deller, Marc C.; Nguyen, Phuong; Farr, Carol L.; Chiu, Hsiu -Ju; Miller, Mitchell D.; et al

    2015-03-30

    NANOG (from Irish mythology Tír na nÓg) transcription factor plays a central role in maintaining pluripotency, cooperating with OCT4 (also known as POU5F1 or OCT3/4), SOX2, and other pluripotency factors. Although the physiological roles of the NANOG protein have been extensively explored, biochemical and biophysical properties in relation to its structural analysis are poorly understood. Here we determined the crystal structure of the human NANOG homeodomain (hNANOG HD) bound to an OCT4 promoter DNA, which revealed amino acid residues involved in DNA recognition that are likely to be functionally important. We generated a series of hNANOG HD alanine substitution mutantsmore » based on the protein–DNA interaction and evolutionary conservation and determined their biological activities. Some mutant proteins were less stable, resulting in loss or decreased affinity for DNA binding. Overexpression of the orthologous mouse NANOG (mNANOG) mutants failed to maintain self-renewal of mouse embryonic stem cells without leukemia inhibitory factor. These results suggest that these residues are critical for NANOG transcriptional activity. Interestingly, one mutant, hNANOG L122A, conversely enhanced protein stability and DNA-binding affinity. The mNANOG L122A, when overexpressed in mouse embryonic stem cells, maintained their expression of self-renewal markers even when retinoic acid was added to forcibly drive differentiation. When overexpressed in epiblast stem cells or human induced pluripotent stem cells, the L122A mutants enhanced reprogramming into ground-state pluripotency. These findings indicate that structural and biophysical information on key transcriptional factors provides insights into the manipulation of stem cell behaviors and a framework for rational protein engineering.« less

  7. MEF promotes stemness in the pathogenesis of gliomas

    PubMed Central

    Bazzoli, Elena; Pulvirenti, Teodoro; Oberstadt, Moritz C.; Perna, Fabiana; Wee, Boyoung; Schultz, Nikolaus; Huse, Jason T.; Fomchenko, Elena I.; Voza, Francesca; Tabar, Viviane; Brennan, Cameron W.; DeAngelis, Lisa M.; Nimer, Stephen D.; Holland, Eric C.; Squatrito, Massimo

    2013-01-01

    Summary High-grade gliomas are aggressive and uniformly fatal tumors, composed of a heterogeneous population of cells that include many with stem cell-like properties. The acquisition of stem-like traits might contribute to glioma initiation, growth and recurrence. Here we investigated the role of the transcription factor myeloid Elf-1 like factor (MEF, also known as ELF4) in glioma. We found that MEF is highly expressed in both human and mouse GBMs and its absence impairs gliomagenesis in a PDGF-driven glioma mouse model. We show that modulation of MEF levels in both mouse neural stem cells and human glioblastoma cells, has a significant impact on neurosphere formation. Moreover, we identify Sox2 as a direct downstream target of MEF. Taken together, our studies implicate MEF as a previously unrecognized gatekeeper gene in gliomagenesis by promoting stem cell characteristics through Sox2 activation. PMID:23217424

  8. Graft of the gelatin sponge scaffold containing genetically-modified neural stem cells promotes cell differentiation, axon regeneration, and functional recovery in rat with spinal cord transection.

    PubMed

    Du, Bao-Ling; Zeng, Xiang; Ma, Yuan-Huan; Lai, Bi-Qin; Wang, Jun-Mei; Ling, Eng-Ang; Wu, Jin-Lang; Zeng, Yuan-Shan

    2015-04-01

    Biological materials combined with genetically-modified neural stem cells (NSCs) are candidate therapy targeting spinal cord injury (SCI). Based on our previous studies, here we performed gelatin sponge (GS) scaffold seeded with neurotrophin-3 (NT-3) and its receptor TrkC gene modifying NSCs for repairing SCI. Eight weeks later, compared with other groups, neurofilament-200 and 5-hydroxytryptamine positive nerve fibers were more in the injury site of the N+T-NSCs group. Immunofluorescence staining showed the grafted NSCs could differentiate into microtubule associated protein (Map2), postsynaptic density (PSD95), and mouse oligodendrocyte special protein (MOSP) positive cells. The percentage of the Map2, PSD95, and MOSP positive cells in the N+T-NSCs group was higher than the other groups. Immuno-electron microscopy showed the grafted NSCs making contact with each other in the injury site. Behavioral analysis indicated the recovery of hindlimbs locomotion was better in the groups receiving cell transplant, the best recovery was found in the N+T-NSCs group. Electrophysiology revealed the amplitude of cortical motor evoked potentials was increased significantly in the N+T-NSCs group, but the latency remained long. These findings suggest the GS scaffold containing genetically-modified NSCs may bridge the injury site, promote axon regeneration and partial functional recovery in SCI rats. PMID:25046856

  9. Gene therapy for canine leukocyte adhesion deficiency with lentiviral vectors using the murine stem cell virus and human phosphoglycerate kinase promoters.

    PubMed

    Hunter, Michael J; Zhao, Huifen; Tuschong, Laura M; Bauer, Thomas R; Burkholder, Tanya H; Persons, Derek A; Hickstein, Dennis D

    2011-06-01

    Children with leukocyte adhesion deficiency type 1 (LAD-1) and dogs with canine LAD (CLAD) develop life-threatening bacterial infections due to mutations in the leukocyte integrin CD18. Here, we compared the human phosphoglycerate kinase (hPGK) promoter to the murine stem cell virus (MSCV) promoter/enhancer in a self-inactivating HIV-1-derived lentiviral vector to treat animals with CLAD. Four CLAD dogs were infused with CD34(+) cells transduced with the hPGK vector, and two CLAD dogs received MSCV vector-transduced CD34(+) cells. Infusions were preceded by a nonmyeloablative dose of 200 cGy total body irradiation. Comparable numbers of transduced cells were infused in each group of animals. Only one of four CLAD animals treated with the hPGK-cCD18 vector had reversal of CLAD, whereas both MSCV-cCD18 vector-treated dogs had reversal of the phenotype. Correction of CLAD depends both upon the percentage of CD18(+) myeloid cells and the level of expression of CD18 on individual myeloid cells. In this regard, the hPGK promoter directed low levels of expression of CD18 on neutrophils compared to the MSCV promoter, likely contributing to the suboptimal clinical outcome with the hPGK vector. PMID:21275758

  10. Gene Therapy for Canine Leukocyte Adhesion Deficiency with Lentiviral Vectors Using the Murine Stem Cell Virus and Human Phosphoglycerate Kinase Promoters

    PubMed Central

    Zhao, Huifen; Tuschong, Laura M.; Bauer, Thomas R.; Burkholder, Tanya H.; Persons, Derek A.; Hickstein, Dennis D.

    2011-01-01

    Abstract Children with leukocyte adhesion deficiency type 1 (LAD-1) and dogs with canine LAD (CLAD) develop life-threatening bacterial infections due to mutations in the leukocyte integrin CD18. Here, we compared the human phosphoglycerate kinase (hPGK) promoter to the murine stem cell virus (MSCV) promoter/enhancer in a self-inactivating HIV-1–derived lentiviral vector to treat animals with CLAD. Four CLAD dogs were infused with CD34+ cells transduced with the hPGK vector, and two CLAD dogs received MSCV vector–transduced CD34+ cells. Infusions were preceded by a nonmyeloablative dose of 200 cGy total body irradiation. Comparable numbers of transduced cells were infused in each group of animals. Only one of four CLAD animals treated with the hPGK-cCD18 vector had reversal of CLAD, whereas both MSCV-cCD18 vector–treated dogs had reversal of the phenotype. Correction of CLAD depends both upon the percentage of CD18+ myeloid cells and the level of expression of CD18 on individual myeloid cells. In this regard, the hPGK promoter directed low levels of expression of CD18 on neutrophils compared to the MSCV promoter, likely contributing to the suboptimal clinical outcome with the hPGK vector. PMID:21275758

  11. ROCK inhibitor Y27632 promotes proliferation and diminishes apoptosis of marmoset induced pluripotent stem cells by suppressing expression and activity of caspase 3.

    PubMed

    Wu, Yuehong; Shu, Jianhong; He, Chengwen; Li, Min; Wang, Yujiong; Ou, Wenbin; He, Yulong

    2016-01-15

    Previous studies reported that Rho-associated kinase inhibitor Y27632 markedly diminishes human embryonic stem cell and induced pluripotent stem cell (iPSC) dissociation-induced apoptosis and increases cloning efficiency in a feeder-free culture system. However, the mechanisms by which Y27632 protects pluripotent stem cells from apoptosis remain unknown. In the present study, we tested the effects of Y27632 on single dissociated marmoset iPSCs in a feeder-free culture. The results showed that Y27632 promoted the number of cells proliferating after passage by single-cell dissociation in a dose-dependent manner. The Rho-associated kinase inhibitor Y27632 markedly increased the cloning efficiency of marmoset iPSCs without affecting their karyotype and the expression of pluripotency markers. Meanwhile, Y27632 markedly diminished apoptosis of the marmoset iPSCs under even more severe conditions by suppressing the expression and activity of caspase 3. Taken together, the present results suggest that this reagent is effective in improving the cultural system of primate iPSCs. PMID:26476594

  12. Plant Stem Cells.

    PubMed

    Greb, Thomas; Lohmann, Jan U

    2016-09-12

    Among the trending topics in the life sciences, stem cells have received a fair share of attention in the public debate - mostly in connection with their potential for biomedical application and therapies. While the promise of organ regeneration and the end of cancer have captured our imagination, it has gone almost unnoticed that plant stem cells represent the ultimate origin of much of the food we eat, the oxygen we breathe, as well the fuels we burn. Thus, plant stem cells may be ranked among the most important cells for human well-being. Research by many labs in the last decades has uncovered a set of independent stem cell systems that fulfill the specialized needs of plant development and growth in four dimensions. Surprisingly, the cellular and molecular design of these systems is remarkably similar, even across diverse species. In some long-lived plants, such as trees, plant stem cells remain active over hundreds or even thousands of years, revealing the exquisite precision in the underlying control of proliferation, self-renewal and differentiation. In this minireview, we introduce the basic features of the three major plant stem cell systems building on these facts, highlight their modular design at the level of cellular layout and regulatory underpinnings and briefly compare them with their animal counterparts. PMID:27623267

  13. Promotion of Expansion and Differentiation of Hematopoietic Stem Cells by Interleukin-27 into Myeloid Progenitors to Control Infection in Emergency Myelopoiesis

    PubMed Central

    Furusawa, Jun-ichi; Mizoguchi, Izuru; Chiba, Yukino; Hisada, Masayuki; Kobayashi, Fumie; Yoshida, Hiroki; Nakae, Susumu; Tsuchida, Akihiko; Matsumoto, Tetsuya; Ema, Hideo; Mizuguchi, Junichiro; Yoshimoto, Takayuki

    2016-01-01

    Emergency myelopoiesis is inflammation-induced hematopoiesis to replenish myeloid cells in the periphery, which is critical to control the infection with pathogens. Previously, pro-inflammatory cytokines such as interferon (IFN)-α and IFN-γ were demonstrated to play a critical role in the expansion of hematopoietic stem cells (HSCs) and myeloid progenitors, leading to production of mature myeloid cells, although their inhibitory effects on hematopoiesis were also reported. Therefore, the molecular mechanism of emergency myelopoiesis during infection remains incompletely understood. Here, we clarify that one of the interleukin (IL)-6/IL-12 family cytokines, IL-27, plays an important role in the emergency myelopoiesis. Among various types of hematopoietic cells in bone marrow, IL-27 predominantly and continuously promoted the expansion of only Lineage−Sca-1+c-Kit+ (LSK) cells, especially long-term repopulating HSCs and myeloid-restricted progenitor cells with long-term repopulating activity, and the differentiation into myeloid progenitors in synergy with stem cell factor. These progenitors expressed myeloid transcription factors such as Spi1, Gfi1, and Cebpa/b through activation of signal transducer and activator of transcription 1 and 3, and had enhanced potential to differentiate into migratory dendritic cells (DCs), neutrophils, and mast cells, and less so into macrophages, and basophils, but not into plasmacytoid DCs, conventional DCs, T cells, and B cells. Among various cytokines, IL-27 in synergy with the stem cell factor had the strongest ability to augment the expansion of LSK cells and their differentiation into myeloid progenitors retaining the LSK phenotype over a long period of time. The experiments using mice deficient for one of IL-27 receptor subunits, WSX-1, and IFN-γ revealed that the blood stage of malaria infection enhanced IL-27 expression through IFN-γ production, and the IL-27 then promoted the expansion of LSK cells, differentiating and

  14. Myogenic differentiation potential of human tonsil-derived mesenchymal stem cells and their potential for use to promote skeletal muscle regeneration

    PubMed Central

    PARK, SAEYOUNG; CHOI, YOONYOUNG; JUNG, NAMHEE; YU, YEONSIL; RYU, KYUNG-HA; KIM, HAN SU; JO, INHO; CHOI, BYUNG-OK; JUNG, SUNG-CHUL

    2016-01-01

    Stem cells are regarded as an important source of cells which may be used to promote the regeneration of skeletal muscle (SKM) which has been damaged due to defects in the organization of muscle tissue caused by congenital diseases, trauma or tumor removal. In particular, mesenchymal stem cells (MSCs), which require less invasive harvesting techniques, represent a valuable source of cells for stem cell therapy. In the present study, we demonstrated that human tonsil-derived MSCs (T-MSCs) may differentiate into myogenic cells in vitro and that the transplantation of myoblasts and myocytes generated from human T-MSCs mediates the recovery of muscle function in vivo. In order to induce myogenic differentiation, the T-MSC-derived spheres were cultured in Dulbecco's modified Eagle's medium/nutrient mixture F-12 (DMEM/F-12) supplemented with 1 ng/ml transforming growth factor-β, non-essential amino acids and insulin-transferrin-selenium for 4 days followed by culture in myogenic induction medium [low-glucose DMEM containing 2% fetal bovine serum (FBS) and 10 ng/ml insulin-like growth factor 1 (IGF1)] for 14 days. The T-MSCs sequentially differentiated into myoblasts and skeletal myocytes, as evidenced by the increased expression of skeletal myogenesis-related markers [including α-actinin, troponin I type 1 (TNNI1) and myogenin] and the formation of myotubes in vitro. The in situ transplantation of T-MSCs into mice with a partial myectomy of the right gastrocnemius muscle enhanced muscle function, as demonstrated by gait assessment (footprint analysis), and restored the shape of SKM without forming teratomas. Thus, T-MSCs may differentiate into myogenic cells and effectively regenerate SKM following injury. These results demonstrate the therapeutic potential of T-MSCs to promote SKM regeneration following injury. PMID:27035161

  15. Myogenic differentiation potential of human tonsil-derived mesenchymal stem cells and their potential for use to promote skeletal muscle regeneration.

    PubMed

    Park, Saeyoung; Choi, Yoonyoung; Jung, Namhee; Yu, Yeonsil; Ryu, Kyung-Ha; Kim, Han Su; Jo, Inho; Choi, Byung-Ok; Jung, Sung-Chul

    2016-05-01

    Stem cells are regarded as an important source of cells which may be used to promote the regeneration of skeletal muscle (SKM) which has been damaged due to defects in the organization of muscle tissue caused by congenital diseases, trauma or tumor removal. In particular, mesenchymal stem cells (MSCs), which require less invasive harvesting techniques, represent a valuable source of cells for stem cell therapy. In the present study, we demonstrated that human tonsil-derived MSCs (T-MSCs) may differentiate into myogenic cells in vitro and that the transplantation of myoblasts and myocytes generated from human T-MSCs mediates the recovery of muscle function in vivo. In order to induce myogenic differentiation, the T-MSC-derived spheres were cultured in Dulbecco's modified Eagle's medium/nutrient mixture F-12 (DMEM/F‑12) supplemented with 1 ng/ml transforming growth factor-β, non-essential amino acids and insulin‑transferrin-selenium for 4 days followed by culture in myogenic induction medium [low-glucose DMEM containing 2% fetal bovine serum (FBS) and 10 ng/ml insulin‑like growth factor 1 (IGF1)] for 14 days. The T-MSCs sequentially differentiated into myoblasts and skeletal myocytes, as evidenced by the increased expression of skeletal myogenesis-related markers [including α-actinin, troponin I type 1 (TNNI1) and myogenin] and the formation of myotubes in vitro. The in situ transplantation of T-MSCs into mice with a partial myectomy of the right gastrocnemius muscle enhanced muscle function, as demonstrated by gait assessment (footprint analysis), and restored the shape of SKM without forming teratomas. Thus, T-MSCs may differentiate into myogenic cells and effectively regenerate SKM following injury. These results demonstrate the therapeutic potential of T-MSCs to promote SKM regeneration following injury. PMID:27035161

  16. Molecular Features of Neural Stem Cells Enable their Enrichment Using Pharmacological Inhibitors of Survival-Promoting Kinases

    PubMed Central

    Brazel, Christine Y.; Alaythan, Abdulaziz A.; Felling, Ryan J.; Calderon, Frances; Levison, Steven W.

    2013-01-01

    Isolating a pure population of neural stem cells (NSCs) has been difficult since no exclusive surface markers have been identified for panning or FACS purification. Moreover, additional refinements for maintaining NSCs in culture are required, since NSCs generate a variety of neural precursors (NPs) as they proliferate. Here, we demonstrate that postnatal rat NPs express low levels of pro-apoptotic molecules and resist PI3K and ERK1/2 inhibition as compared to late oligodendrocyte progenitors. Furthermore, maintaining SVZ precursors in LY294002 and PD98059, inhibitors of PI3K and ERK1/2 signaling, eliminated lineage-restricted precursors as revealed by enrichment for Nestin+/SOX-2+ cells. The cells that survived formed neurospheres and 89% of these neurospheres were tripotential, generating neurons, astrocytes and oligodendrocytes. Without this enrichment step, less than 50% of the NPs were Nestin+/SOX-2+ and 42% of the neurospheres were tripotential. Additionally, neurospheres enriched using this procedure produced 3-times more secondary neurospheres, supporting the conclusion that this procedure enriches for NSCs. A number of genes that enhance survival were more highly expressed in neurospheres compared to late oligodendrocyte progenitors. Altogether, these studies demonstrate that primitive neural precursors can be enriched using a relatively simple and inexpensive means that will facilitate cell replacement strategies using stem cells as well as other studies whose goal is to reveal the fundamental properties of primitive neural precursors. PMID:24032666

  17. Hypoxia promotes CEMP1 expression and induces cementoblastic differentiation of human dental stem cells in an HIF-1-dependent manner.

    PubMed

    Choi, Hwajung; Jin, Hexiu; Kim, Jin-Young; Lim, Ki-Taek; Choung, Han-Wool; Park, Joo-Young; Chung, Jong Hoon; Choung, Pill-Hoon

    2014-01-01

    Cementum covering the tooth root provides attachment for the tooth proper to the surrounding alveolar bone via non-mineralized periodontal ligament (PDL). Cementum protein 1 (CEMP1) has been shown to induce a cementoblastic phenotype in cementoblast precursors cells of PDL. Oxygen availability is a critical signal for correct development of many tissues; however, its role in tooth root and periodontium development remains poorly understood. In this study, we demonstrated that reduced oxygen tension increased CEMP1 expression, mineral deposition, and alkaline phosphatase activity in human dental stem cells such as PDL stem cells and periapical follicular stem cells. Since an oxemic state is transduced by the transcription factor, hypoxia-inducible factor-1 (HIF-1), we performed experiments to determine whether this protein was responsible for the observed changes. We noted that when HIF-1 was activated by gene introduction or chemically, CEMP1 expression and mineralization increased. In contrast, when HIF-1α was silenced, CEMP1 expression and mineralization did not increase in vitro. Furthermore, we showed for the first time that mouse tooth root and periodontium development occurs partly under hypoxic conditions, particularly at the apical part and latently at the PDL space in vivo. Desferrioxamine, an HIF-1 stimulator, enhances CEMP1 expression in the mouse PDL space, suggesting that hypoxia affects cementogenesis of PDL cells lining the surface of the developing tooth root in an HIF-1-dependent manner. These results suggest that HIF-1 activators may have the ability to stimulate regeneration of the tooth root and cementum formation. PMID:24117017

  18. Stem cell strategies for Alzheimer's disease therapy.

    PubMed

    Sugaya, K; Alvarez, A; Marutle, A; Kwak, Y D; Choumkina, E

    2006-06-01

    We have found much evidence that the brain is capable of regenerating neurons after maturation. In our previous study, human neural stem cells (HNSCs) transplanted into aged rat brains differentiated into neural cells and significantly improved the cognitive functions of the animals, indicating that HNSCs may be a promising candidate for cell-replacement therapies for neurodegenerative diseases including Alzheimer's disease (AD). However, ethical and practical issues associated with HNSCs compel us to explore alternative strategies. Here, we report novel technologies to differentiate adult human mesenchymal stem cells, a subset of stromal cells in the bone marrow, into neural cells by modifying DNA methylation or over expression of nanog, a homeobox gene expressed in embryonic stem cells. We also report peripheral administrations of a pyrimidine derivative that increases endogenous stem cell proliferation improves cognitive function of the aged animal. Although these results may promise a bright future for clinical applications used towards stem cell strategies in AD therapy, we must acknowledge the complexity of AD. We found that glial differentiation takes place in stem cells transplanted into amyloid-( precursor protein (APP) transgenic mice. We also found that over expression of APP gene or recombinant APP treatment causes glial differentiation of stem cells. Although further detailed mechanistic studies may be required, RNA interference of APP or reduction of APP levels in the brain can significantly reduced glial differentiation of stem cells and may be useful in promoting neurogenesis after stem cell transplantation. PMID:16953146

  19. rFN/Cad-11-Modified Collagen Type II Biomimetic Interface Promotes the Adhesion and Chondrogenic Differentiation of Mesenchymal Stem Cells

    PubMed Central

    Guo, Hongfeng; Zhang, Yuan; Li, Zhengsheng; Kang, Fei; Yang, Bo; Kang, Xia; Wen, Can; Yan, Yanfei; Jiang, Bo; Fan, Yujiang

    2013-01-01

    Properties of the cell-material interface are determining factors in the successful function of cells for cartilage tissue engineering. Currently, cell adhesion is commonly promoted through the use of polypeptides; however, due to their lack of complementary or modulatory domains, polypeptides must be modified to improve their ability to promote adhesion. In this study, we utilized the principle of matrix-based biomimetic modification and a recombinant protein, which spans fragments 7–10 of fibronectin module III (heterophilic motif ) and extracellular domains 1–2 of cadherin-11 (rFN/Cad-11) (homophilic motif ), to modify the interface of collagen type II (Col II) sponges. We showed that the designed material was able to stimulate cell proliferation and promote better chondrogenic differentiation of rabbit mesenchymal stem cells (MSCs) in vitro than both the FN modified surfaces and the negative control. Further, the Col II/rFN/Cad-11-MSCs composite stimulated cartilage formation in vivo; the chondrogenic effect of Col II alone was much less significant. These results suggested that the rFN/Cad-11-modified collagen type II biomimetic interface has dual biological functions of promoting adhesion and stimulating chondrogenic differentiation. This substance, thus, may serve as an ideal scaffold material for cartilage tissue engineering, enhancing repair of injured cartilage in vivo. PMID:23919505

  20. KDM5B focuses H3K4 methylation near promoters and enhancers during embryonic stem cell self-renewal and differentiation

    PubMed Central

    2014-01-01

    Background Pluripotency of embryonic stem (ES) cells is controlled in part by chromatin-modifying factors that regulate histone H3 lysine 4 (H3K4) methylation. However, it remains unclear how H3K4 demethylation contributes to ES cell function. Results Here, we show that KDM5B, which demethylates lysine 4 of histone H3, co-localizes with H3K4me3 near promoters and enhancers of active genes in ES cells; its depletion leads to spreading of H3K4 methylation into gene bodies and enhancer shores, indicating that KDM5B functions to focus H3K4 methylation at promoters and enhancers. Spreading of H3K4 methylation to gene bodies and enhancer shores is linked to defects in gene expression programs and enhancer activity, respectively, during self-renewal and differentiation of KDM5B-depleted ES cells. KDM5B critically regulates H3K4 methylation at bivalent genes during differentiation in the absence of LIF or Oct4. We also show that KDM5B and LSD1, another H3K4 demethylase, co-regulate H3K4 methylation at active promoters but they retain distinct roles in demethylating gene body regions and bivalent genes. Conclusions Our results provide global and functional insight into the role of KDM5B in regulating H3K4 methylation marks near promoters, gene bodies, and enhancers in ES cells and during differentiation. PMID:24495580

  1. EIF2S3Y suppresses the pluripotency state and promotes the proliferation of mouse embryonic stem cells

    PubMed Central

    Li, Na; Mu, Hailong; Zheng, Liming; Li, Bo; Wu, Chongyang; Niu, Bowen; Shen, Qiaoyan; He, Xin; Hua, Jinlian

    2016-01-01

    Eukaryotic translation initiation factor 2, subunit 3, and structural gene Y-linked (EIF2S3Y) is essential for spermatogenesis in mouse models. However, its effect on embryonic stem (ES) cells remains unknown. In our observation, differentiated ES cells showed higher levels of EIF2S3Y. To further elucidate its role in ES cells, we utilized ES-derived EIF2S3Y-overexpressing cells and found that EIF2S3Y down-regulated the pluripotency state of ES cells, which might be explained by decreased histone methylation levels because of reduced levels of ten-eleven translocation 1 (TET1). Moreover, EIF2S3Y-overexpressing cells showed an enhanced proliferation rate, which might be due to increased Cyclin A and Cyclin E levels. This study highlighted novel roles of EIF2S3Y in the pluripotency maintenance and proliferation control of ES cells, which would provide an efficient model to study germ cell generation as well as cancer development using ES cells, thus providing valuable target for clinical applications of ES cells. PMID:26863630

  2. Inhibition of mitogen-activated protein kinase kinase, DNA methyltransferase, and transforming growth factor-β promotes differentiation of human induced pluripotent stem cells into enterocytes.

    PubMed

    Kodama, Nao; Iwao, Takahiro; Kabeya, Tomoki; Horikawa, Takashi; Niwa, Takuro; Kondo, Yuki; Nakamura, Katsunori; Matsunaga, Tamihide

    2016-06-01

    We previously reported that small-molecule compounds were effective in generating pharmacokinetically functional enterocytes from human induced pluripotent stem (iPS) cells. In this study, to determine whether the compounds promote the differentiation of human iPS cells into enterocytes, we investigated the effects of a combination of mitogen-activated protein kinase kinase (MEK), DNA methyltransferase (DNMT), and transforming growth factor (TGF)-β inhibitors on intestinal differentiation. Human iPS cells cultured on feeder cells were differentiated into endodermal cells by activin A. These endodermal-like cells were then differentiated into intestinal stem cells by fibroblast growth factor 2. Finally, the cells were differentiated into enterocyte cells by epidermal growth factor and small-molecule compounds. After differentiation, mRNA expression levels and drug-metabolizing enzyme activities were measured. The mRNA expression levels of the enterocyte marker sucrase-isomaltase and the major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 were increased by a combination of MEK, DNMT, and TGF-β inhibitors. The mRNA expression of CYP3A4 was markedly induced by 1α,25-dihydroxyvitamin D3. Metabolic activities of CYP1A1/2, CYP2B6, CYP2C9, CYP2C19, CYP3A4/5, UDP-glucuronosyltransferase, and sulfotransferase were also observed in the differentiated cells. In conclusion, MEK, DNMT, and TGF-β inhibitors can be used to promote the differentiation of human iPS cells into pharmacokinetically functional enterocytes. PMID:27161454

  3. The Src homology 2 protein Shb promotes cell cycle progression in murine hematopoietic stem cells by regulation of focal adhesion kinase activity

    SciTech Connect

    Gustafsson, Karin; Heffner, Garrett; Wenzel, Pamela L.; Curran, Matthew; Grawé, Jan; McKinney-Freeman, Shannon L.; Daley, George Q.; Welsh, Michael

    2013-07-15

    The widely expressed adaptor protein Shb has previously been reported to contribute to T cell function due to its association with the T cell receptor and furthermore, several of Shb's known interaction partners are established regulators of blood cell development and function. In addition, Shb deficient embryonic stem cells displayed reduced blood cell colony formation upon differentiation in vitro. The aim of the current study was therefore to explore hematopoietic stem and progenitor cell function in the Shb knockout mouse. Shb deficient bone marrow contained reduced relative numbers of long-term hematopoietic stem cells (LT-HSCs) that exhibited lower proliferation rates. Despite this, Shb knockout LT-HSCs responded promptly by entering the cell cycle in response to genotoxic stress by 5-fluorouracil treatment. In competitive LT-HSC transplantations, Shb null cells initially engrafted as well as the wild-type cells but provided less myeloid expansion over time. Moreover, Shb knockout bone marrow cells exhibited elevated basal activities of focal adhesion kinase/Rac1/p21-activated kinase signaling and reduced responsiveness to Stem Cell Factor stimulation. Consequently, treatment with a focal adhesion kinase inhibitor increased Shb knockout LT-HSC proliferation. The altered signaling characteristics thus provide a plausible mechanistic explanation for the changes in LT-HSC proliferation since these signaling intermediates have all been shown to participate in LT-HSC cell cycle control. In summary, the loss of Shb dependent signaling in bone marrow cells, resulting in elevated focal adhesion kinase activity and reduced proliferative responses in LT-HSCs under steady state hematopoiesis, confers a disadvantage to the maintenance of LT-HSCs over time. -- Highlights: • Shb is an adaptor protein operating downstream of tyrosine kinase receptors. • Shb deficiency reduces hematopoietic stem cell proliferation. • The proliferative effect of Shb occurs via increased

  4. Aneuploidy in stem cells

    PubMed Central

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to reality. However, as somatic cells might have accumulated various chromosomal abnormalities, including aneuploidies throughout their lives, the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated, or worse, become at risk of adopting a malignant fate. In this review, we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore, we review the differences between how somatic cells and stem cells respond to aneuploidy. PMID:27354891

  5. Aquaporin 3 promotes the stem-like properties of gastric cancer cells via Wnt/GSK-3β/β-catenin pathway

    PubMed Central

    Zhao, Haijian; Dong, Xuqiang; Zhang, Zhihong; Wang, Shoulin; Shen, Lizong

    2016-01-01

    Cancer stem cells (CSCs) are believed to contribute to the tumor growth in gastric carcinoma (GC), a common lethal malignancy. This study investigated the effect of aquaporin 3 (AQP3) on stem-like properties of human GC cells. Elevated AQP3 expression was associated with CD44 expression in human GC specimens. Expression of AQP3 and that of CD44 positively correlated with Lauren classification, lymph node metastasis, and lymphovascular invasion. Altering the AQP3 expression had pronounced effects on the tumorigenic potential and self-renewal capacity of the gastric cancer cell lines SGC7901, MGC803, and AGS, both in vitro and in vivo. Overexpression of AQP3 induced CD44 expression and activation of the β-catenin signaling pathway, whereas silencing AQP3 expression using short hairpin RNA had the opposite effect. Furthermore, pharmacological inhibition of GSK-3β using LiCl impaired the effect of AQP3 knockdown in CSCs, whereas the inhibition of the Wnt/β-catenin pathway by XAV939 blocked the effect of AQP3 overexpression. These results demonstrate that AQP3 promotes stem-like properties of human GC cells by activating the Wnt/GSK-3β/β-catenin signaling pathway. PMID:26918728

  6. GRAM domain-containing protein 1A (GRAMD1A) promotes the expansion of hepatocellular carcinoma stem cell and hepatocellular carcinoma growth through STAT5.

    PubMed

    Fu, Binsheng; Meng, Wei; Zhao, Hui; Zhang, Bing; Tang, Hui; Zou, Ying; Yao, Jia; Li, Heping; Zhang, Tong

    2016-01-01

    Hepatocellular carcinoma (HCC) is the leading cause for cancer death worldwide, new prognostic factors and targets are critical for HCC treatment. Here, we found GRAMD1A was upregulated in HCC tissues, patients with high GRAMD1A levels had poor outcome, statistical analyses found GRAMD1A expression was positively correlated with pathologic differentiation and survival or mortality. It was an unfavorable prognostic factor for HCC patients. Functional analyses revealed GRAMD1A contributed to the self-renewal of HCC stem cells, resistance to chemotherapy and tumor growth of HCC determined by hepatosphere formation assay, side population (SP) analysis, TUNEL assay, soft agar growth ability assay and tumor growth model in vivo. Mechanism analyses found signal transducer and activator of transcription 5 (STAT5) was the target of GRAMD1A, GRAMD1A regulated the target genes of STAT5 and the transcriptional activity of STAT5. Inhibition of STAT5 in indicated HCC cells overexpressing GRAMD1A suppressed the effects of GRAMD1A on the self-renewal of HCC stem cell, resistance to chemotherapy and tumor growth, suggesting GRAMD1A promoted the self-renewal of HCC stem cells and the development of HCC by increasing STAT5 level. GRAMD1A might be a useful biomarker and target for HCC. PMID:27585821

  7. Human amniotic epithelial stem cells promote wound healing by facilitating migration and proliferation of keratinocytes via ERK, JNK and AKT signaling pathways.

    PubMed

    Zhao, Bin; Liu, Jia-Qi; Zheng, Zhao; Zhang, Jun; Wang, Shu-Yue; Han, Shi-Chao; Zhou, Qin; Guan, Hao; Li, Chao; Su, Lin-Lin; Hu, Da-Hai

    2016-07-01

    Wound healing is a highly orchestrated physiological process consisting in a complex interaction of cellular and biochemical events. Human amniotic epithelial stem cells (HAESCs) have been shown to be an attractive resource for wound healing because they are primitive stem cells. However, the exact effects of amnion-derived stem cells on the migration or proliferation of keratinocytes and their potential mechanism are not fully understood. We have found that HAESCs accelerate the migration of keratinocytes and induce a remarkable increase in the activity of phospho-ERK, phospho-JNK, and phospho-AKT, the blockade of which by their specific inhibitors significantly inhibits migration induced by HAESC-conditioned medium (CM). Furthermore, the co-culture of keratinocytes with HAESCs up-regulates the expression levels of cell proliferation proteins Cyclin D1, Cyclin D3 and Mdm2. In vivo animal experiments have shown that HAESC-CM improves wound healing, whereas blockade with ERK, JNK and AKT inhibitors significantly impairs wound healing. Taken together, these results reveal, for the first time, that HAESCs promote wound healing by facilitating the migration and proliferation of keratinocytes via ERK, JNK and AKT signaling pathways and might be a potential therapy in skin wound healing. PMID:26888423

  8. GRAM domain-containing protein 1A (GRAMD1A) promotes the expansion of hepatocellular carcinoma stem cell and hepatocellular carcinoma growth through STAT5

    PubMed Central

    Fu, Binsheng; Meng, Wei; Zhao, Hui; Zhang, Bing; Tang, Hui; Zou, Ying; Yao, Jia; Li, Heping; Zhang, Tong

    2016-01-01

    Hepatocellular carcinoma (HCC) is the leading cause for cancer death worldwide, new prognostic factors and targets are critical for HCC treatment. Here, we found GRAMD1A was upregulated in HCC tissues, patients with high GRAMD1A levels had poor outcome, statistical analyses found GRAMD1A expression was positively correlated with pathologic differentiation and survival or mortality. It was an unfavorable prognostic factor for HCC patients. Functional analyses revealed GRAMD1A contributed to the self-renewal of HCC stem cells, resistance to chemotherapy and tumor growth of HCC determined by hepatosphere formation assay, side population (SP) analysis, TUNEL assay, soft agar growth ability assay and tumor growth model in vivo. Mechanism analyses found signal transducer and activator of transcription 5 (STAT5) was the target of GRAMD1A, GRAMD1A regulated the target genes of STAT5 and the transcriptional activity of STAT5. Inhibition of STAT5 in indicated HCC cells overexpressing GRAMD1A suppressed the effects of GRAMD1A on the self-renewal of HCC stem cell, resistance to chemotherapy and tumor growth, suggesting GRAMD1A promoted the self-renewal of HCC stem cells and the development of HCC by increasing STAT5 level. GRAMD1A might be a useful biomarker and target for HCC. PMID:27585821

  9. Knockdown of a HIF-2α promoter upstream long noncoding RNA impairs colorectal cancer stem cell properties in vitro through HIF-2α downregulation.

    PubMed

    Yao, Jie; Li, Jianxiong; Geng, Peiliang; Li, Yi; Chen, Hong; Zhu, Yunfeng

    2015-01-01

    Currently, various long noncoding RNAs (lncRNAs) have been identified as key regulators of multiple cancers. However, cancer stem cell (CSC)-related lncRNAs have rarely been reported. In this study, we found an lncRNA that is a promoter upstream transcript of hypoxia-inducible factor-2α (HIF-2α), and we named it "lncRNA-HIF2PUT". The function of HIF-2α is closely connected with "stem cell-like" properties, and the function of PROMPTs is often associated with the adjacent protein-coding transcripts. Herein, we showed that the expression of lncRNA-HIF2PUT was significantly correlated with HIF-2α in colorectal cancer (CRC) tissues. Knockdown of lncRNA-HIF2PUT blocked the HIF-2α expression and inhibited the CSC properties in CRC cell lines DLD-1 and HT29. LncRNA-HIF2PUTsmall interfering RNA transfection resulted in decreased stemness genes expression, impaired colony formation, and spheroid formation ability, retarded migration, and invasion of the cells. These data suggest that lncRNA-HIF2PUT may be a regulator of HIF-2α and a mediator of CSCs in CRC. PMID:26648739

  10. Knockdown of a HIF-2α promoter upstream long noncoding RNA impairs colorectal cancer stem cell properties in vitro through HIF-2α downregulation

    PubMed Central

    Yao, Jie; Li, Jianxiong; Geng, Peiliang; Li, Yi; Chen, Hong; Zhu, Yunfeng

    2015-01-01

    Currently, various long noncoding RNAs (lncRNAs) have been identified as key regulators of multiple cancers. However, cancer stem cell (CSC)-related lncRNAs have rarely been reported. In this study, we found an lncRNA that is a promoter upstream transcript of hypoxia-inducible factor-2α (HIF-2α), and we named it “lncRNA-HIF2PUT”. The function of HIF-2α is closely connected with “stem cell-like” properties, and the function of PROMPTs is often associated with the adjacent protein-coding transcripts. Herein, we showed that the expression of lncRNA-HIF2PUT was significantly correlated with HIF-2α in colorectal cancer (CRC) tissues. Knockdown of lncRNA-HIF2PUT blocked the HIF-2α expression and inhibited the CSC properties in CRC cell lines DLD-1 and HT29. LncRNA-HIF2PUTsmall interfering RNA transfection resulted in decreased stemness genes expression, impaired colony formation, and spheroid formation ability, retarded migration, and invasion of the cells. These data suggest that lncRNA-HIF2PUT may be a regulator of HIF-2α and a mediator of CSCs in CRC. PMID:26648739

  11. Priming with ceramide-1 phosphate promotes the therapeutic effect of mesenchymal stem/stromal cells on pulmonary artery hypertension.

    PubMed

    Lim, Jisun; Kim, YongHwan; Heo, Jinbeom; Kim, Kang-Hyun; Lee, Seungun; Lee, Sei Won; Kim, Kyunggon; Kim, In-Gyu; Shin, Dong-Myung

    2016-04-22

    Some molecules enriched in damaged organs can contribute to tissue repair by stimulating the mobilization of stem cells. These so-called "priming" factors include bioactive lipids, complement components, and cationic peptides. However, their therapeutic significance remains to be determined. Here, we show that priming of mesenchymal stromal/stem cells (MSCs) with ceramide-1 phosphate (C1P), a bioactive lipid, enhances their therapeutic efficacy in pulmonary artery hypertension (PAH). Human bone marrow (BM)-derived MSCs treated with 100 or 200 μM C1P showed improved migration activity in Transwell assays compared with non-primed MSCs and concomitantly activated MAPK(p42/44) and AKT signaling cascades. Although C1P priming had little effect on cell surface marker phenotypes and the multipotency of MSCs, it potentiated their proliferative, colony-forming unit-fibroblast, and anti-inflammatory activities. In a monocrotaline-induced PAH animal model, a single administration of human MSCs primed with C1P significantly attenuated the PAH-related increase in right ventricular systolic pressure, right ventricular hypertrophy, and thickness of α-smooth muscle actin-positive cells around the vessel wall. Thus, this study shows that C1P priming increases the effects of MSC therapy by enhancing the migratory, self-renewal, and anti-inflammatory activity of MSCs and that MSC therapy optimized with priming protocols might be a promising option for the treatment of PAH patients. PMID:26993164

  12. Knockdown of DNMT1 and DNMT3a Promotes the Angiogenesis of Human Mesenchymal Stem Cells Leading to Arterial Specific Differentiation.

    PubMed

    Zhang, Rui; Wang, Nan; Zhang, Li-Nan; Huang, Na; Song, Tie-Feng; Li, Zheng-Zheng; Li, Man; Luo, Xue-Gang; Zhou, Hao; He, Hong-Peng; Zhang, Xiao-Yu; Ma, Wenjian; Zhang, Tong-Cun

    2016-05-01

    Human mesenchymal stem cells (hMSCs) possess the potential to differentiate into endothelial cells (EC). DNA methylation plays an important role in cell differentiation during development. However, the role of the DNA methyltransferases Dnmt1 and Dnmt3a in specific arterial differentiation of hMSCs is not clear. Here, we show that the CpG islands in the promoter regions of the EC specification and arterial marker genes were highly methylated in hMSCs based on bisulfite genomic sequencing. Treatment with the DNMT inhibitor 5-aza-dc induced the reactivation of EC specification and arterial marker genes by promoting demethylation of these genes as well as stimulating tube-like structure formation. The hMSCs with stable knockdown of Dnmt1/Dnmt3a were highly angiogenic and expressed several arterial specific transcription factors and marker genes. A Matrigel plug assay confirmed that Dnmt1/Dnmt3a stable knockdown hMSCs enhanced blood vessel formation compared with WT MSCs. We also identified that the transcription factor E2F1 could upregulate the transcription of arterial marker genes by binding to the promoters of arterial genes, suggesting its critical role for arterial specification. Moreover, miRNA gain/loss-of-function analyses revealed that miR152 and miR30a were involved in endothelial differentiation of hMSCs by targeting Dnmt1 and Dnmt3a, respectively. Taken together, these data suggest that Dnmt1 and Dnmt3a are critical regulators for epigenetic silencing of EC marker genes and that E2F1 plays an important role in promoting arterial cell determination. Stem Cells 2016;34:1273-1283. PMID:26850336

  13. A small molecule inhibitor of SRC family kinases promotes simple epithelial differentiation of human pluripotent stem cells.

    PubMed

    Lian, Xiaojun; Selekman, Joshua; Bao, Xiaoping; Hsiao, Cheston; Zhu, Kexian; Palecek, Sean P

    2013-01-01

    Human pluripotent stem cells (hPSCs) provide unprecedented opportunities to study the earliest stages of human development in vitro and have the potential to provide unlimited new sources of cells for regenerative medicine. Although previous studies have reported cytokeratin 14+/p63+ keratinocyte generation from hPSCs, the multipotent progenitors of epithelial lineages have not been described and the developmental pathways regulating epithelial commitment remain largely unknown. Here we report membrane localization of β-catenin during retinoic acid (RA)--induced epithelial differentiation. In addition hPSC treatment with the Src family kinase inhibitor SU6656 modulated β-catenin localization and produced an enriched population of simple epithelial cells under defined culture conditions. SU6656 strongly upregulated expression of cytokeratins 18 and 8 (K18/K8), which are expressed in simple epithelial cells, while repressing expression of the pluripotency gene Oct4. This homogeneous population of K18+K8+Oct4- simple epithelial precursor cells can further differentiate into cells expressing keratinocyte or corneal-specific markers. These enriched hPSC-derived simple epithelial cells may provide a ready source for development and toxicology cell models and may serve as a progenitor for epithelial cell transplantation applications. PMID:23527294

  14. Dental pulp stem cells

    PubMed Central

    Ashri, Nahid Y.; Ajlan, Sumaiah A.; Aldahmash, Abdullah M.

    2015-01-01

    Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable scaffold, and guided through signaling molecules. Dental pulp stem cells have been used in an increasing number of studies in dental tissue engineering. Those cells show mesenchymal (stromal) stem cell-like properties including self-renewal and multilineage differentiation potentials, aside from their relative accessibility and pleasant handling properties. The purpose of this article is to review the biological principles of periodontal tissue engineering, along with the challenges facing the development of a consistent and clinically relevant tissue regeneration platform. This article includes an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors. PMID:26620980

  15. Bortezomib and Filgrastim in Promoting Stem Cell Mobilization in Patients With Non-Hodgkin Lymphoma or Multiple Myeloma Undergoing Stem Cell Transplant

    ClinicalTrials.gov

    2016-04-19

    Adult Grade III Lymphomatoid Granulomatosis; B-cell Chronic Lymphocytic Leukemia; Contiguous Stage II Adult Burkitt Lymphoma; Contiguous Stage II Adult Diffuse Large Cell Lymphoma; Contiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Contiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Contiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Contiguous Stage II Adult Lymphoblastic Lymphoma; Contiguous Stage II Grade 1 Follicular Lymphoma; Contiguous Stage II Grade 2 Follicular Lymphoma; Contiguous Stage II Grade 3 Follicular Lymphoma; Contiguous Stage II Mantle Cell Lymphoma; Contiguous Stage II Marginal Zone Lymphoma; Contiguous Stage II Small Lymphocytic Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Noncontiguous Stage II Adult Burkitt Lymphoma; Noncontiguous Stage II Adult Diffuse Large Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Mixed Cell Lymphoma; Noncontiguous Stage II Adult Diffuse Small Cleaved Cell Lymphoma; Noncontiguous Stage II Adult Immunoblastic Large Cell Lymphoma; Noncontiguous Stage II Adult Lymphoblastic Lymphoma; Noncontiguous Stage II Grade 1 Follicular Lymphoma; Noncontiguous Stage II Grade 2 Follicular Lymphoma; Noncontiguous Stage II Grade 3 Follicular Lymphoma; Noncontiguous Stage II Mantle Cell Lymphoma; Noncontiguous Stage II Marginal Zone Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Progressive Hairy Cell Leukemia, Initial Treatment; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular

  16. mTOR signaling promotes stem cell activation via counterbalancing BMP-mediated suppression during hair regeneration.

    PubMed

    Deng, Zhili; Lei, Xiaohua; Zhang, Xudong; Zhang, Huishan; Liu, Shuang; Chen, Qi; Hu, Huimin; Wang, Xinyue; Ning, Lina; Cao, Yujing; Zhao, Tongbiao; Zhou, Jiaxi; Chen, Ting; Duan, Enkui

    2015-02-01

    Hair follicles (HFs) undergo cycles of degeneration (catagen), rest (telogen), and regeneration (anagen) phases. Anagen begins when the hair follicle stem cells (HFSCs) obtain sufficient activation cues to overcome suppressive signals, mainly the BMP pathway, from their niche cells. Here, we unveil that mTOR complex 1 (mTORC1) signaling is activated in HFSCs, which coincides with the HFSC activation at the telogen-to-anagen transition. By using both an inducible conditional gene targeting strategy and a pharmacological inhibition method to ablate or inhibit mTOR signaling in adult skin epithelium before anagen initiation, we demonstrate that HFs that cannot respond to mTOR signaling display significantly delayed HFSC activation and extended telogen. Unexpectedly, BMP signaling activity is dramatically prolonged in mTOR signaling-deficient HFs. Through both gain- and loss-of-function studies in vitro, we show that mTORC1 signaling negatively affects BMP signaling, which serves as a main mechanism whereby mTORC1 signaling facilitates HFSC activation. Indeed, in vivo suppression of BMP by its antagonist Noggin rescues the HFSC activation defect in mTORC1-null skin. Our findings reveal a critical role for mTOR signaling in regulating stem cell activation through counterbalancing BMP-mediated repression during hair regeneration. PMID:25609845

  17. Transplanted Oligodendrocytes and Motoneuron Progenitors Generated from Human Embryonic Stem Cells Promote Locomotor Recovery After Spinal Cord Transection

    PubMed Central

    Erceg, Slaven; Ronaghi, Mohammad; Oria, Marc; García Roselló, Mireia; Aragó, Maria Amparo Pérez; Lopez, Maria Gomez; Radojevic, Ivana; Moreno-Manzano, Victoria; Rodríguez-Jiménez, Francisco-Javier; Shanker Bhattacharya, Shom; Cordoba, Juan; Stojkovic, Miodrag

    2010-01-01

    Human embryonic stem cells (hESC) hold great promise for the treatment of patients with many neurodegenerative diseases particularly those arising from cell loss or neural dysfunction including spinal cord injury. This study evaluates the therapeutic effects of transplanted hESC-derived oligodendrocyte progenitors (OPC) and/or motoneuron progenitors (MP) on axonal remyelination and functional recovery of adult rats after complete spinal cord transection. OPC and/or MP were grafted into the site of injury in the acute phase. Based on Basso-Beattie-Bresnahan scores recovery of locomotor function was significantly enhanced in rats treated with OPC and/or MP when compared with control animals. When transplanted into the spinal cord immediately after complete transection, OPC and MP survived, migrated, and differentiated into mature oligodendrocytes and neurons showing in vivo electrophysiological activity. Taken together, these results indicate that OPC and MP derived from hESC could be a useful therapeutic strategy to repair injured spinal cord. Stem Cells 2010; 28:1541–1549. PMID:20665739

  18. DOT1L Activity Promotes Proliferation and Protects Cortical Neural Stem Cells from Activation of ATF4-DDIT3-Mediated ER Stress In Vitro.

    PubMed

    Roidl, Deborah; Hellbach, Nicole; Bovio, Patrick P; Villarreal, Alejandro; Heidrich, Stefanie; Nestel, Sigrun; Grüning, Björn A; Boenisch, Ulrike; Vogel, Tanja

    2016-01-01

    Growing evidence suggests that the lysine methyltransferase DOT1L/KMT4 has important roles in proliferation, survival, and differentiation of stem cells in development and in disease. We investigated the function of DOT1L in neural stem cells (NSCs) of the cerebral cortex. The pharmacological inhibition and shRNA-mediated knockdown of DOT1L impaired proliferation and survival of NSCs. DOT1L inhibition specifically induced genes that are activated during the unfolded protein response (UPR) in the endoplasmic reticulum (ER). Chromatin-immunoprecipitation analyses revealed that two genes encoding for central molecules involved in the ER stress response, Atf4 and Ddit3 (Chop), are marked with H3K79 methylation. Interference with DOT1L activity resulted in transcriptional activation of both genes accompanied by decreased levels of H3K79 dimethylation. Although downstream effectors of the UPR, such as Ppp1r15a/Gadd34, Atf3, and Tnfrsf10b/Dr5 were also transcriptionally activated, this most likely occurred in response to increased ATF4 expression rather than as a direct consequence of altered H3K79 methylation. While stem cells are particularly vulnerable to stress, the UPR and ER stress have not been extensively studied in these cells yet. Since activation of the ER stress program is also implicated in directing stem cells into differentiation or to maintain a proliferative status, the UPR must be tightly regulated. Our and published data suggest that histone modifications, including H3K4me3, H3K14ac, and H3K79me2, are implicated in the control of transcriptional activation of ER stress genes. In this context, the loss of H3K79me2 at the Atf4- and Ddit3-promoters appears to mark a point-of-no-return that activates the death program in NSCs. PMID:26299268

  19. Human umbilical cord mesenchymal stem cells: a new era for stem cell therapy.

    PubMed

    Ding, Dah-Ching; Chang, Yu-Hsun; Shyu, Woei-Cherng; Lin, Shinn-Zong

    2015-01-01

    The human umbilical cord is a promising source of mesenchymal stem cells (HUCMSCs). Unlike bone marrow stem cells, HUCMSCs have a painless collection procedure and faster self-renewal properties. Different derivation protocols may provide different amounts and populations of stem cells. Stem cell populations have also been reported in other compartments of the umbilical cord, such as the cord lining, perivascular tissue, and Wharton's jelly. HUCMSCs are noncontroversial sources compared to embryonic stem cells. They can differentiate into the three germ layers that promote tissue repair and modulate immune responses and anticancer properties. Thus, they are attractive autologous or allogenic agents for the treatment of malignant and nonmalignant solid and soft cancers. HUCMCs also can be the feeder layer for embryonic stem cells or other pluripotent stem cells. Regarding their therapeutic value, storage banking system and protocols should be established immediately. This review critically evaluates their therapeutic value, challenges, and future directions for their clinical applications. PMID:25622293

  20. Reversing breast cancer stem cell into breast somatic stem cell.

    PubMed

    Wijaya, L; Agustina, D; Lizandi, A O; Kartawinata, M M; Sandra, F

    2011-02-01

    Stem cells have an important role in cell biology, allowing tissues to be renewed by freshly created cells throughout their lifetime. The specific micro-environment of stem cells is called stem cell niche; this environment influences the development of stem cells from quiescence through stages of differentiation. Recent advance researches have improved the understanding of the cellular and molecular components of the micro-environment--or niche--that regulates stem cells. We point out an important trend to the study of niche activity in breast cancers. Breast cancer has long been known to conserve a heterogeneous population of cells. While the majority of cells that make up tumors are destined to differentiate and eventually stop dividing, only minority populations of cells, termed cancer stem cell, possess extensive self renewal capability. These cancer stem cells possess characteristics of both stem cells and cancer cells. Breast cancer stem cells reversal to breast somatic stem cells offer a new therapy, that not only can stop the spread of breast cancer cells, but also can differentiate breast cancer stem cells into normal breast somatic stem cells. These can replace damaged breast tissue. Nevertheless, the complexity of realizing this therapy approach needs further research. PMID:21044008

  1. Activated Thyroid Hormone Promotes Differentiation and Chemotherapeutic Sensitization of Colorectal Cancer Stem Cells by Regulating Wnt and BMP4 Signaling.

    PubMed

    Catalano, Veronica; Dentice, Monica; Ambrosio, Raffaele; Luongo, Cristina; Carollo, Rosachiara; Benfante, Antonina; Todaro, Matilde; Stassi, Giorgio; Salvatore, Domenico

    2016-03-01

    Thyroid hormone is a pleiotropic factor that controls many cellular processes in multiple cell types such as cancer stem cells (CSC). Thyroid hormone concentrations in the blood are stable, but the action of the deiodinases (D2-D3) provides cell-specific regulation of thyroid hormone activity. Deregulation of deiodinase function and thyroid hormone status has been implicated in tumorigenesis. Therefore, we investigated the role of thyroid hormone metabolism and signaling in colorectal CSCs (CR-CSC), where deiodinases control cell division and chemosensitivity. We found that increased intracellular thyroid hormone concentration through D3 depletion induced cell differentiation and sharply mitigated tumor formation. Upregulated BMP4 expression and concomitantly attenuated Wnt signaling accompanied these effects. Furthermore, we demonstrate that BMP4 is a direct thyroid hormone target and is involved in a positive autoregulatory feedback loop that modulates thyroid hormone signaling. Collectively, our findings highlight a cell-autonomous metabolic mechanism by which CR-CSCs exploit thyroid hormone signaling to facilitate their self-renewal potential and suggest that drug-induced cell differentiation may represent a promising therapy for preventing CSC expansion and tumor progression. PMID:26676745

  2. Human umbilical cord blood mononuclear cells and chorionic plate-derived mesenchymal stem cells promote axon survival in a rat model of optic nerve crush injury

    PubMed Central

    CHUNG, SOKJOONG; RHO, SEUNGSOO; KIM, GIJIN; KIM, SO-RA; BAEK, KWANG-HYUN; KANG, MYUNGSEO; LEW, HELEN

    2016-01-01

    The use of mesenchymal stem cells (MSCs) in cell therapy in regenerative medicine has great potential, particularly in the treatment of nerve injury. Umbilical cord blood (UCB) reportedly contains stem cells, which have been widely used as a hematopoietic source and may have therapeutic potential for neurological impairment. Although ongoing research is dedicated to the management of traumatic optic nerve injury using various measures, novel therapeutic strategies based on the complex underlying mechanisms responsible for optic nerve injury, such as inflammation and/or ischemia, are required. In the present study, a rat model of optic nerve crush (ONC) injury was established in order to examine the effects of transplanting human chorionic plate-derived MSCs (CP-MSCs) isolated from the placenta, as well as human UCB mononuclear cells (CB-MNCs) on compressed rat optic nerves. Expression markers for inflammation, apoptosis, and optic nerve regeneration were analyzed, as well as the axon survival rate by direct counting. Increased axon survival rates were observed following the injection of CB-MNCs at at 1 week post-transplantation compared with the controls. The levels of growth-associated protein-43 (GAP-43) were increased after the injection of CB-MNCs or CP-MSCs compared with the controls, and the expression levels of hypoxia-inducible factor-1α (HIF-1α) were also significantly increased following the injection of CB-MNCs or CP-MSCs. ERM-like protein (ERMN) and SLIT-ROBO Rho GTPase activating protein 2 (SRGAP2) were found to be expressed in the optic nerves of the CP-MSC-injected rats with ONC injury. The findings of our study suggest that the administration of CB-MNCs or CP-MSCs may promote axon survival through systemic concomitant mechanisms involving GAP-43 and HIF-1α. Taken together, these findings provide further understanding of the mechanisms repsonsible for optic nerve injury and may aid in the development of novel cell-based therapeutic strategies with

  3. Safeguarding Stem Cell-Based Regenerative Therapy against Iatrogenic Cancerogenesis: Transgenic Expression of DNASE1, DNASE1L3, DNASE2, DFFB Controlled By POLA1 Promoter in Proliferating and Directed Differentiation Resisting Human Autologous Pluripotent Induced Stem Cells Leads to their Death

    PubMed Central

    Malecki, Marek; LaVanne, Christine; Alhambra, Dominique; Dodivenaka, Chaitanya; Nagel, Sarah; Malecki, Raf

    2014-01-01

    Introduction The worst possible complication of using stem cells for regenerative therapy is iatrogenic cancerogenesis. The ultimate goal of our work is to develop a self-triggering feedback mechanism aimed at causing death of all stem cells, which resist directed differentiation, keep proliferating, and can grow into tumors. Specific aim The specific aim was threefold: (1) to genetically engineer the DNA constructs for the human, recombinant DNASE1, DNASE1L3, DNASE2, DFFB controlled by POLA promoter; (2) to bioengineer anti-SSEA-4 antibody guided vectors delivering transgenes to human undifferentiated and proliferating pluripotent stem cells; (3) to cause death of proliferating and directed differentiation resisting stem cells by transgenic expression of the human recombinant the DNases (hrDNases). Methods The DNA constructs for the human, recombinant DNASE1, DNASE1L3, DNASE2, DFFB controlled by POLA promoter were genetically engineered. The vectors targeting specifically SSEA-4 expressing stem cells were bioengineered. The healthy volunteers’ bone marrow mononuclear cells (BMMCs) were induced into human, autologous, pluripotent stem cells with non-integrating plasmids. Directed differentiation of the induced stem cells into endothelial cells was accomplished with EGF and BMP. The anti-SSEA 4 antibodies’ guided DNA vectors delivered the transgenes for the human recombinant DNases’ into proliferating stem cells. Results Differentiation of the pluripotent induced stem cells into the endothelial cells was verified by highlighting formation of tight and adherens junctions through transgenic expression of recombinant fluorescent fusion proteins: VE cadherin, claudin, zona occludens 1, and catenin. Proliferation of the stem cells was determined through highlighting transgenic expression of recombinant fluorescent proteins controlled by POLA promoter, while also reporting expression of the transgenes for the hrDNases. Expression of the transgenes for the DNases

  4. Dimethyloxaloylglycine Increases the Bone Healing Capacity of Adipose-Derived Stem Cells by Promoting Osteogenic Differentiation and Angiogenic Potential

    PubMed Central

    Ding, Hao; Gao, You-Shui; Wang, Yang; Hu, Chen

    2014-01-01

    Hypoxia inducible factor-1α (HIF-1α) plays an important role in angiogenesis-osteogenesis coupling during bone regeneration, which can enhance the bone healing capacity of mesenchymal stem cells (MSCs) by improving their osteogenic and angiogenic activities. Previous studies transduced the HIF-1α gene into MSCs with lentivirus vectors to improve their bone healing capacity. However, the risks due to lentivirus vectors, such as tumorigenesis, should be considered before clinical application. Dimethyloxaloylglycine (DMOG) is a cell-permeable prolyl-4-hydroxylase inhibitor, which can activate the expression of HIF-1α in cells at normal oxygen tension. Therefore, DMOG is expected to be an alternative strategy for enhancing HIF-1α expression in cells. In this study, we explored the osteogenic and angiogenic activities of adipose-derived stem cells (ASCs) treated with different concentrations of DMOG in vitro, and the bone healing capacity of DMOG-treated ASCs combined with hydrogels for treating critical-sized calvarial defects in rats. The results showed that DMOG had no obvious cytotoxic effects on ASCs and could inhibit the death of ASCs induced by serum deprivation. DMOG markedly increased vascular endothelial growth factor production in ASCs in a dose-dependent manner and improved the osteogenic differentiation potential of ASCs by activating the expression of HIF-1α. Rats with critical-sized calvarial defects treated with hydrogels containing DMOG-treated ASCs had more bone regeneration and new vessel formation than the other groups. Therefore, we believe that DMOG enhanced the angiogenic and osteogenic activity of ASCs by activating the expression of HIF-1α, thereby improving the bone healing capacity of ASCs in rat critical-sized calvarial defects. PMID:24328551

  5. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2009-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  6. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2002-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  7. Catalyzing stem cell research.

    PubMed

    Willemse, Lisa; Lyall, Drew; Rudnicki, Michael

    2008-09-01

    In 2001, the Stem Cell Network was the first of its kind, a bold initiative to forge and nurture pan-Canadian collaborations involving researchers, engineers, clinicians and private and public sector partners. Canada's broad and deep pool of stem cell talent proved to be a fertile ground for such an initiative, giving rise to a strong, thriving network that, 7 years later, can list innovative cell expansion and screening technologies, early-phase clinical trials for stroke, pulmonary hypertension, muscular dystrophy and cornea replacement, and leading discourse on ethical, legal and social issues among its accomplishments. As it moves into its second and final phase of funding, the Stem Cell Network continues to push boundaries and has set its sights on overcoming the obstacles that impede the transfer of research findings to clinical applications, commercial products and public policy. PMID:18729799

  8. Electrical stimulation using conductive polymer polypyrrole promotes differentiation of human neural stem cells: a biocompatible platform for translational neural tissue engineering.

    PubMed

    Stewart, Elise; Kobayashi, Nao R; Higgins, Michael J; Quigley, Anita F; Jamali, Sina; Moulton, Simon E; Kapsa, Robert M I; Wallace, Gordon G; Crook, Jeremy M

    2015-04-01

    Conductive polymers (CPs) are organic materials that hold great promise for biomedicine. Potential applications include in vitro or implantable electrodes for excitable cell recording and stimulation and conductive scaffolds for cell support and tissue engineering. In this study, we demonstrate the utility of electroactive CP polypyrrole (PPy) containing the anionic dopant dodecylbenzenesulfonate (DBS) to differentiate novel clinically relevant human neural stem cells (hNSCs). Electrical stimulation of PPy(DBS) induced hNSCs to predominantly β-III Tubulin (Tuj1) expressing neurons, with lower induction of glial fibrillary acidic protein (GFAP) expressing glial cells. In addition, stimulated cultures comprised nodes or clusters of neurons with longer neurites and greater branching than unstimulated cultures. Cell clusters showed a similar spatial distribution to regions of higher conductivity on the film surface. Our findings support the use of electrical stimulation to promote neuronal induction and the biocompatibility of PPy(DBS) with hNSCs and opens up the possibility of identifying novel mechanisms of fate determination of differentiating human stem cells for advanced in vitro modeling, translational drug discovery, and regenerative medicine. PMID:25296166

  9. Dimethyloxaloylglycine Promotes the Angiogenic Activity of Mesenchymal Stem Cells Derived from iPSCs via Activation of the PI3K/Akt Pathway for Bone Regeneration

    PubMed Central

    Zhang, Jieyuan; Guan, Junjie; Qi, Xin; Ding, Hao; Yuan, Hong; Xie, Zongping; Chen, Chunyuan; Li, Xiaolin; Zhang, Changqing; Huang, Yigang

    2016-01-01

    The vascularization of tissue-engineered bone is a prerequisite step for the successful repair of bone defects. Hypoxia inducible factor-1α (HIF-1α) plays an essential role in angiogenesis-osteogenesis coupling during bone regeneration and can activate the expression of angiogenic factors in mesenchymal stem cells (MSCs). Dimethyloxaloylglycine (DMOG) is an angiogenic small molecule that can inhibit prolyl hydroxylase (PHD) enzymes and thus regulate the stability of HIF-1α in cells at normal oxygen tension. Human induced pluripotent stem cell-derived MSCs (hiPSC-MSCs) are promising alternatives for stem cell therapy. In this study, we evaluated the effect of DMOG on promoting hiPSC-MSCs angiogenesis in tissue-engineered bone and simultaneously explored the underlying mechanisms in vitro. The effectiveness of DMOG in improving the expression of HIF-1α and its downstream angiogenic genes in hiPSC-MSCs demonstrated that DMOG significantly enhanced the gene and protein expression profiles of angiogenic-related factors in hiPSC-MSCs by sustaining the expression of HIF-1α. Further analysis showed that DMOG-stimulated hiPSC-MSCs angiogenesis was associated with the phosphorylation of protein kinase B (Akt) and with an increase in VEGF production. The effects could be blocked by the addition of the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. In a critical-sized calvarial defect model in rats, DMOG-treated hiPSC-MSCs showed markedly improved angiogenic capacity in the tissue-engineered bone, leading to bone regeneration. Collectively, the results indicate that DMOG, via activation of the PI3K/Akt pathway, promotes the angiogenesis of hiPSC-MSCs in tissue-engineered bone for bone defect repair and that DMOG-treated hiPSC-MSCs can be exploited as a potential therapeutic tool in bone regeneration. PMID:27194942

  10. Bone-Marrow-Derived Mesenchymal Stem Cells Promote Proliferation and Neuronal Differentiation of Niemann–Pick Type C Mouse Neural Stem Cells by Upregulation and Secretion of CCL2

    PubMed Central

    Lee, Hyun; Kang, Ji Eun; Lee, Jong Kil; Bae, Jae-sung

    2013-01-01

    Abstract Niemann–Pick type C (NP-C) disease is a neurodegenerative disorder characterized neuropathologically by ballooned neurons distended with lipid storage and widespread neuronal loss. Neural stem cells (NSC) derived from NP-C disease models have decreased ability for self-renewal and neuronal differentiation. Investigation of neurogenesis in the adult brain has suggested that NP-C disease can be overcome, or at least ameliorated, by the generation of new neurons. Bone-marrow-derived mesenchymal stem cells (BM-MSCs) are regarded as potential candidates for use in the treatment of neurodegenerative disorders because of their ability to promote neurogenesis. The underlying mechanisms of BM-MSC-induced promotion of neurogenesis, however, have not been resolved. The aim of the present study was to examine the mechanism of neurogenesis by BM-MSCs in NP-C disease. Coculture of embryonic NSCs from NP-C mice that exhibit impaired ability for self-renewal and decreased rates of neuronal differentiation with BM-MSCs resulted in an enhanced capacity for self-renewal and an increased ability for differentiation into neurons or oligodendrocytes. In addition, results of in vivo studies have demonstrated that transplantation of intracerebral BM-MSCs resulted in stimulated proliferation and neuronal differentiation of NSCs within the subventricular zone. Of particular interest, enhanced proliferation and neuronal differentiation of endogenous NP-C mouse NSCs showed an association with elevated release of the chemokine (C-C motif) ligand 2 (CCL2) from BM-MSCs. These effects suggest that soluble CCL2 derived from BM-MSCs can modulate endogenous NP-C NSCs, resulting in their improved proliferation and neuronal differentiation in mice. PMID:23659480

  11. Claulansine F promoted the neuronal differentiation of neural stem and progenitor cells through Akt/GSK-3β/β-catenin pathway.

    PubMed

    Huang, Ju-Yang; Ma, Yin-Zhong; Yuan, Yu-He; Zuo, Wei; Chu, Shi-Feng; Liu, Hang; Du, Guan-Hua; Zhang, Dong-Ming; Chen, Nai-Hong

    2016-09-01

    The persistence of neurogenesis raises the idea that neurons produced by the resident or transplanted neural stem cells could replace the neurons lost from brain injury or neurodegenerative disease. Therefore, compounds or methods for promoting neuronal differentiation become the focus of neurodegenerative disease therapy research. Claulansine F (Clau F), a newly discovered carbazole alkaloid, has been showed to induce neuritogenesis in PC12 cells. Herein, we studied the effect of Clau F on neuronal differentiation of neural stem/progenitor cells (NS/PCs). The current study demonstrated that Clau F initiated neuronal differentiation with a significant increase of TuJ1-positive cells and TuJ1 protein levels. We also found that Clau F promoted the maturity and sustainability of neurons by increasing MAP2-positive cells and MAP2 protein levels. At the same time, Clau F significantly inhibited the proliferation of NS/PCs. The underlying mechanism of Clau F was preliminary explored. Clau F treatment resulted in a profound increase of phosphorylation of Akt and GSK-3β, which led to GSK-3β inhibition and subsequently the nuclear accumulation of β-catenin. Further, the interaction between β-catenin and p300 in the nucleus was enhanced and the transcription of p300/β-catenin responsive genes were increased significantly (c-jun, fra-1) by Clau F. Importantly, the positive effect of Clau F on neuronal differentiation was abolished by Akti-1/2, a specific inhibitor of Akt-1/2 kinase, which indicated the involvement of Akt/GSK-3β in Clau F-mediated neuronal differentiation. In conclusion, these data suggested that Clau F promoted neuronal differentiation through Akt/GSK-3β/β-catenin signaling pathway in NS/PCs. PMID:27179990

  12. BMP2 is superior to BMP4 for promoting human muscle-derived stem cell-mediated bone regeneration in a critical-sized calvarial defect model.

    PubMed

    Gao, Xueqin; Usas, Arvydas; Lu, Aiping; Tang, Ying; Wang, Bing; Chen, Chien-Wen; Li, Hongshuai; Tebbets, Jessica C; Cummins, James H; Huard, Johnny

    2013-01-01

    Muscle-derived cells have been successfully isolated using a variety of different methods and have been shown to possess multilineage differentiation capacities, including an ability to differentiate into articular cartilage and bone in vivo; however, the characterization of human muscle-derived stem cells (hMDSCs) and their bone regenerative capacities have not been fully investigated. Genetic modification of these cells may enhance their osteogenic capacity, which could potentially be applied to bone regenerative therapies. We found that hMDSCs, isolated by the preplate technique, consistently expressed the myogenic marker CD56, the pericyte/endothelial cell marker CD146, and the mesenchymal stem cell markers CD73, CD90, CD105, and CD44 but did not express the hematopoietic stem cell marker CD45, and they could undergo osteogenic, chondrogenic, adipogenic, and myogenic differentiation in vitro. In order to investigate the osteoinductive potential of hMDSCs, we constructed a retroviral vector expressing BMP4 and GFP and a lentiviral vector expressing BMP2. The BMP4-expressing hMDSCs were able to undergo osteogenic differentiation in vitro and exhibited enhanced mineralization compared to nontransduced cells; however, when transplanted into a calvarial defect, they failed to regenerate bone. Local administration of BMP4 protein and cell pretreatment with N-acetylcysteine (NAC), which improves cell survival, did not enhance the osteogenic capacity of the retro-BMP4-transduced cells. In contrast, lenti-BMP2-transduced hMDSCs not only exhibited enhanced in vitro osteogenic differentiation but also induced robust bone formation and nearly completely healed a critical-sized calvarial defect in CD-1 nude mice 6 weeks following transplantation. Herovici's staining of the regenerated bone demonstrated that the bone matrix contained a large amount of type I collagen. Our findings indicated that the hMDSCs are likely mesenchymal stem cells of muscle origin and that BMP2 is

  13. Scx-transduced tendon-derived stem cells (tdscs) promoted better tendon repair compared to mock-transduced cells in a rat patellar tendon window injury model.

    PubMed

    Tan, Chunlai; Lui, Pauline Po Yee; Lee, Yuk Wa; Wong, Yin Mei

    2014-01-01

    We hypothesized that the transplantation of Scx-transduced tendon-derived stem cells (TDSCs) promoted better tendon repair compared to the transplantation of mock-transduced cells. This study thus aimed to investigate the effect of Scx transduction on the expression of lineage markers in TDSCs and the effect of the resulting cell line in the promotion of tendon repair. Rat non-GFP or GFP-TDSCs were transduced with Scx or empty lentiviral vector (Mock) and selected by blasticidin. The mRNA expressions of Scx and different lineage markers were examined by qRT-PCR. The effect of the transplantation of GFP-TDSC-Scx on tendon repair was then tested in a rat unilateral patellar tendon window injury model. The transplantation of GFP-TDSC-Mock and scaffold-only served as controls. At week 2, 4 and 8 post-transplantation, the repaired patellar tendon was harvested for ex vivo fluorescent imaging, vivaCT imaging, histology, immunohistochemistry and biomechanical test. GFP-TDSC-Scx consistently showed higher expressions of most of tendon- and cartilage- related markers compared to the GFP-TDSC-Mock. However, the effect of Scx transduction on the expressions of bone-related markers was inconclusive. The transplanted GFP-TDSCs could be detected in the window wound at week 2 but not at week 4. Ectopic mineralization was detected in some samples at week 8 but there was no difference among different groups. The GFP-TDSC-Scx group only statistically significantly improved tendon repair histologically and biomechanically compared to the Scaffold-only group and the GFP-TDSC-Mock group at the early stage of tendon repair. There was significant higher expression of collagen type I in the window wound in the GFP-TDSC-Scx group compared to the other two groups at week 2. The transplantation of GFP-TDSC-Scx promoted healing at the early stage of tendon repair in a rat patellar tendon window injury model. PMID:24831949

  14. Epigenetic Alterations of IL-6/STAT3 Signaling by Placental Stem Cells Promote Hepatic Regeneration in a Rat Model with CCl4-induced Liver Injury

    PubMed Central

    Jung, Jieun; Moon, Ji Wook; Choi, Jong-Ho; Lee, Yong Woo; Park, Sun-Hwa; Kim, Gi Jin

    2015-01-01

    Background Human chorionic plate-derived mesenchymal stem cells (CP-MSCs) isolated from the placenta have been reported to demonstrate therapeutic effects in animal models of liver injury; however, the underlying epigenetic mechanism of this effect has not been elucidated. Thus, we investigated whether CP-MSCs influence epigenetic processes during regeneration of the injured liver. Methods CP-MSCs were engrafted into a carbon tetrachloride (CCl4)-injured rat model through direct transplantation into the liver (DTX), intrasplenic transplantation (STX), and intravenous transplantation via the tail vein (TTX). Non-transplanted (NTX) rats were maintained as sham controls. Liver tissues were analyzed after transplantation using immunohistochemistry, western blot analysis, and quantitative methylation-specific polymerase chain reaction. Proliferation and human interleukin-6 (hIL-6) enzyme-linked immunosorbent assays were performed using CCl4-treated hepatic cells that were co-cultured with CP-MSCs. Results The Ki67 labeling index, cell cyclins, albumin, IL-6, and gp130 levels were elevated in the CP-MSC transplantation groups. The concentration of hIL-6 in supernatants and the proliferation of CCl4-treated rat hepatic cells were enhanced by co-culturing with CP-MSCs (p<0.05), while the methylation of IL-6/IL-6R and STAT3 by CP-MSC transplantation decreased. Conclusion These results suggest that administration of CP-MSCs promotes IL-6/STAT3 signaling by decreasing the methylation of the IL-6/SATA3 promoters and thus inducing the proliferation of hepatic cells in a CCl4-injured liver rat model. These data advance our understanding of the therapeutic mechanisms in injured livers, and can facilitate the development of cell-based therapies using placenta-derived stem cells. PMID:26019757

  15. Chemotherapy targeting cancer stem cells

    PubMed Central

    Liu, Haiguang; Lv, Lin; Yang, Kai

    2015-01-01

    Conventional chemotherapy is the main treatment for cancer and benefits patients in the form of decreased relapse and metastasis and longer overall survival. However, as the target therapy drugs and delivery systems are not wholly precise, it also results in quite a few side effects, and is less efficient in many cancers due to the spared cancer stem cells, which are considered the reason for chemotherapy resistance, relapse, and metastasis. Conventional chemotherapy limitations and the cancer stem cell hypothesis inspired our search for a novel chemotherapy targeting cancer stem cells. In this review, we summarize cancer stem cell enrichment methods, the search for new efficient drugs, and the delivery of drugs targeting cancer stem cells. We also discuss cancer stem cell hierarchy complexity and the corresponding combination therapy for both cancer stem and non-stem cells. Learning from cancer stem cells may reveal novel strategies for chemotherapy in the future. PMID:26045975

  16. Conditioned Media from Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Inhibits Melanogenesis by Promoting Proteasomal Degradation of MITF

    PubMed Central

    Lim, Hoon; Shin, Ji Hyun; Park, So Jung; Jo, Yoon Kyung; Oh, Wonil; Yang, Yoon Sun; Cho, Dong-Hyung; Kim, Ju-Yeon

    2015-01-01

    Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) secrete various beneficial molecules, which have anti-apoptotic activity and cell proliferation. However, the effect of hUCB-MSCs in melanogenesis is largely unclear. In this study, we show that conditioned media (CM) derived from hUCB-MSCs inhibit melanogenesis by regulating microphthalmia-associated transcription factor (MITF) expression via the ERK signalling pathway. Treatment of hUCB-MSC-CM strongly inhibited the alpha-melanocyte stimulating hormone-induced hyperpigmentation in melanoma cells as well as melanocytes. Treatment of hUCB-MSC-CM induced ERK1/2 activation in melanocytes. In addition, inhibition of ERK1/2 suppressed the anti-pigmentation activity of the hUCB-MSC-CM in melanocytes and in vitro artificial skin models. We also found that the expression of MITF was appreciably diminished while expression of phosphorylated MITF, which leads to its proteasomal degradation, was increased in cells treated with hUCB-MSC-CM. These results suggested that hUCB-MSC-CM significantly suppresses melanin synthesis via MITF degradation by the ERK pathway activation. PMID:26024475

  17. Poly-L-ornithine promotes preferred differentiation of neural stem/progenitor cells via ERK signalling pathway

    PubMed Central

    Ge, Hongfei; Tan, Liang; Wu, Pengfei; Yin, Yi; Liu, Xin; Meng, Hui; Cui, Gaoyu; Wu, Nan; Lin, Jiangkai; Hu, Rong; Feng, Hua

    2015-01-01

    Neural stem/progenitor cells (NSPCs) replacement therapies are the most attractive strategies to restore an injured brain. Key challenges of such therapies are enriching NSPCs and directing them differentiation into specific neural cell types. Here, three biomaterial substrates Poly-L-ornithine (PO), Poly-L-lysine (PLL) and fibronectin (FN) were investigated for their effects on proliferation and differentiation of rat NSPCs, and the underlying mechanisms were also explored. The results showed PO significantly increased NSPCs proliferation and induced preferred differentiation, compared with PLL and FN. Checking protein markers of several neural cell subtypes, it is showed PO significantly induced NSPCs expressing Doublecortin (DCX) and Olig2, one for neuroblasts and young neurons and the other for young oligodendrocytes. It is suggested the ERK signaling pathway was involving in this process because an ERK antagonist U0126 could inhibit PO’s effects mentioned above, as well as an ERK pathway agonist Ceramide C6 could enhance them. Given that both neurons and oligodendrocytes are the most vulnerable cells in many neurological diseases, PO-induced preferred differentiation into neurons and oligodendrocytes is a potential paradigm for NSPCs-based therapies. PMID:26503112

  18. Porous Membrane Substrates Offer Better Niches to Enhance the Wnt Signaling and Promote Human Embryonic Stem Cell Growth and Differentiation

    PubMed Central

    Yao, Huantong; Krisanarungson, Pantrika; Haukas, Andreas; Ye, Kaiming

    2012-01-01

    Human embryonic stem cells (hESCs) require specific niches for adhesion, expansion, and lineage-specific differentiation. In this study, we showed that a membrane substrate offers better tissue niches for hESC attachment, spreading, proliferation, and differentiation. The cell doubling time was shortened from 46.3±5.7 h for hESCs grown on solid substrates to 25.6±2.6 h for those on polyester (PE) membrane substrates with pore size of 0.4 μm. In addition, we observed an increase of approximately five- to ninefold of definitive endoderm marker gene expression in hESCs differentiated on PE or polyethylene terephthalate membrane substrates. Global gene expression analysis revealed upregulated expressions of a number of extracellular matrix and cell adhesion molecules in hESCs grown on membrane substrates. Further, an enhanced nuclear translocation of β-catenin was detected in these cells. These observations suggested the augmentation of Wnt signaling in hESCs grown on membrane substrates. These results also demonstrated that a membrane substrate can offer better physicochemical cues for enhancing in vitro hESC attachment, proliferation, and differentiation. PMID:22429220

  19. Poly-L-ornithine promotes preferred differentiation of neural stem/progenitor cells via ERK signalling pathway

    NASA Astrophysics Data System (ADS)

    Ge, Hongfei; Tan, Liang; Wu, Pengfei; Yin, Yi; Liu, Xin; Meng, Hui; Cui, Gaoyu; Wu, Nan; Lin, Jiangkai; Hu, Rong; Feng, Hua

    2015-10-01

    Neural stem/progenitor cells (NSPCs) replacement therapies are the most attractive strategies to restore an injured brain. Key challenges of such therapies are enriching NSPCs and directing them differentiation into specific neural cell types. Here, three biomaterial substrates Poly-L-ornithine (PO), Poly-L-lysine (PLL) and fibronectin (FN) were investigated for their effects on proliferation and differentiation of rat NSPCs, and the underlying mechanisms were also explored. The results showed PO significantly increased NSPCs proliferation and induced preferred differentiation, compared with PLL and FN. Checking protein markers of several neural cell subtypes, it is showed PO significantly induced NSPCs expressing Doubl