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Sample records for stem cells overexpressing

  1. Transplantation of CXCR4 Overexpressed Mesenchymal Stem Cells Augments Regeneration in Degenerated Intervertebral Discs.

    PubMed

    Wei, Ji-Nan; Cai, Feng; Wang, Feng; Wu, Xiao-Tao; Liu, Lei; Hong, Xin; Tang, Wen-Hao

    2016-05-01

    SDF-1/CXCR4 chemotaxis signals play important roles in regulating the stem cell-based tissue regeneration. The aim of this research is to evaluate whether high expression of CXCR4 enhances the migration of mesenchymal stem cells (MSCs) and increases the efficiency of intervertebral disc (IVD) regeneration. MSCs overexpressing CXCR (CXCR4-MSC) were created by lentiviral-CXCR4-vect transfection, labeled with SPIO, and transplanted into rabbit degenerative IVD induced by annulus puncture. X-ray and T2-weighted MR images of the spine were obtained at 0, 8, and 16 weeks post-transplantation. The transplanted stem cells were traced by both MR imaging and Prussian blue staining. The stem cell-based IVD degeneration was evaluated by quantifying the expression of aggrecan and type II collagen. The in vitro chemotaxis test was performed to study the migration of CXCR4-MSCs to the supplement of SDF-1. The CXCR4-overexpressing MSCs stably elevated the expression of CXCR4 and increased the migration to SDF-1. The SPIO-labeled CXCR4-MSC could be detected within the IVD by MRI till 16 weeks post-transplantation. Prussian blue staining evidenced more SPIO-positive cells within the IVD transplanted with CXCR4-MSCs. Compared to the control group, loss of disc height was slowed while the mRNA expression of aggrecan and type II collagen was increased by MSC transplantation, especially in the IVD supplemented with CXCR4-MSCs. CXCR4 overexpression promoted MSC retention within the IVD and enhanced the stem cell-based IVD regeneration. The SDF-1/CXCR4 chemotaxis signals might help provide a new perspective to understand stem cell migration and infiltration within the degenerated IVD. PMID:26788981

  2. Overexpression of SOCS3 inhibits astrogliogenesis and promotes maintenance of neural stem cells.

    PubMed

    Cao, Fang; Hata, Ryuji; Zhu, Pengxiang; Ma, Yong-Jie; Tanaka, Junya; Hanakawa, Yasushi; Hashimoto, Koji; Niinobe, Michio; Yoshikawa, Kazuaki; Sakanaka, Masahiro

    2006-07-01

    To investigate the effects of suppressors of cytokine signaling 3 (SOCS3) on neural stem cell fate, stem cells were infected with an adenoviral vector expressing SOCS3. Three days later, western blot analysis and immunocytochemical analysis revealed that the protein level of MAP2 and the number of MAP2-positive cells were significantly increased in SOCS3-transfected cells, whereas the protein level of GFAP and the number of GFAP-positive cells were significantly decreased. Furthermore, promoter assay revealed a significant reduction in the transcriptional level of signal transducer and activator of transcription 3 (Stat3) in the transfected cells. In addition, the mRNA levels of Notch family member (notch1) and inhibitory basic helix-loop-helix (bHLH) factors (hes5 and id3) were significantly up-regulated 1 day after overexpression of SOCS3. Three days after transfection, the mRNA level of hes5 was significantly decreased, whereas that of notch1 was still up-regulated. Moreover, all of SOCS3-positive cells expressed Nestin protein but did not express MAP2 or GFAP proteins. These data indicate that overexpression of SOCS3 induced neurogenesis and inhibited astrogliogenesis in neural stem cells. Our data also show that SOCS3 promoted maintenance of neural stem cells.

  3. A mouse embryonic stem cell bank for inducible overexpression of human chromosome 21 genes

    PubMed Central

    2010-01-01

    Background Dosage imbalance is responsible for several genetic diseases, among which Down syndrome is caused by the trisomy of human chromosome 21. Results To elucidate the extent to which the dosage imbalance of specific human chromosome 21 genes perturb distinct molecular pathways, we developed the first mouse embryonic stem (ES) cell bank of human chromosome 21 genes. The human chromosome 21-mouse ES cell bank includes, in triplicate clones, 32 human chromosome 21 genes, which can be overexpressed in an inducible manner. Each clone was transcriptionally profiled in inducing versus non-inducing conditions. Analysis of the transcriptional response yielded results that were consistent with the perturbed gene's known function. Comparison between mouse ES cells containing the whole human chromosome 21 (trisomic mouse ES cells) and mouse ES cells overexpressing single human chromosome 21 genes allowed us to evaluate the contribution of single genes to the trisomic mouse ES cell transcriptome. In addition, for the clones overexpressing the Runx1 gene, we compared the transcriptome changes with the corresponding protein changes by mass spectroscopy analysis. Conclusions We determined that only a subset of genes produces a strong transcriptional response when overexpressed in mouse ES cells and that this effect can be predicted taking into account the basal gene expression level and the protein secondary structure. We showed that the human chromosome 21-mouse ES cell bank is an important resource, which may be instrumental towards a better understanding of Down syndrome and other human aneuploidy disorders. PMID:20569505

  4. Overexpression of NTRK1 Promotes Differentiation of Neural Stem Cells into Cholinergic Neurons

    PubMed Central

    Wang, Limin; He, Feng; Zhong, Zhuoyuan; Lv, Ruiyan; Xiao, Songhua; Liu, Zhonglin

    2015-01-01

    Neurotrophic tyrosine kinase type 1 (NTRK1) plays critical roles in proliferation, differentiation, and survival of cholinergic neurons; however, it remains unknown whether enhanced expression of NTRK1 in neural stem cells (NSCs) can promote their differentiation into mature neurons. In this study, a plasmid encoding the rat NTRK1 gene was constructed and transfected into C17.2 mouse neural stem cells (NSCs). NTRK1 overexpression in C17.2 cells was confirmed by western blot. The NSCs overexpressing NTRK1 and the C17.2 NSCs transfected by an empty plasmid vector were treated with or without 100 ng/mL nerve growth factor (NGF) for 7 days. Expression of the cholinergic cell marker, choline acetyltransferase (ChAT), was detected by florescent immunocytochemistry (ICC). In the presence of NGF induction, the NSCs overexpressing NTRK1 differentiated into ChAT-immunopositive cells at 3-fold higher than the NSCs transfected by the plasmid vector (26% versus 9%, P < 0.05). The data suggest that elevated NTRK1 expression increases differentiation of NSCs into cholinergic neurons under stimulation of NGF. The approach also represents an efficient strategy for generation of cholinergic neurons. PMID:26509167

  5. Induced overexpression of OCT4A in human embryonic stem cells increases cloning efficiency.

    PubMed

    Tsai, Steven C; Chang, David F; Hong, Chang-Mu; Xia, Ping; Senadheera, Dinithi; Trump, Lisa; Mishra, Suparna; Lutzko, Carolyn

    2014-06-15

    Our knowledge of the molecular mechanisms underlying human embryonic stem cell (hESC) self-renewal and differentiation is incomplete. The level of octamer-binding transcription factor 4 (Oct4), a critical regulator of pluripotency, is precisely controlled in mouse embryonic stem cells. However, studies of human OCT4 are often confounded by the presence of three isoforms and six expressed pseudogenes, which has complicated the interpretation of results. Using an inducible lentiviral overexpression and knockdown system to manipulate OCT4A above or below physiological levels, we specifically examine the functional role of the OCT4A isoform in hESC. (We also designed and generated a comparable series of vectors, which were not functional, for the overexpression and knockdown of OCT4B.) We show that specific knockdown of OCT4A results in hESC differentiation, as indicated by morphology changes, cell surface antigen expression, and upregulation of ectodermal genes. In contrast, inducible overexpression of OCT4A in hESC leads to a transient instability of the hESC phenotype, as indicated by changes in morphology, cell surface antigen expression, and transcriptional profile, that returns to baseline within 5 days. Interestingly, sustained expression of OCT4A past 5 days enhances hESC cloning efficiency, suggesting that higher levels of OCT4A can support self-renewal. Overall, our results indicate that high levels of OCT4A increase hESC cloning efficiency and do not induce differentiation (whereas OCT4B expression cannot be induced in hESC), highlighting the importance of isoform-specific studies in a stable and inducible expression system for human OCT4. Additionally, we demonstrate the utility of an efficient method for conditional gene expression in hESC.

  6. Silencing KRAS overexpression in arsenic-transformed prostate epithelial and stem cells partially mitigates malignant phenotype.

    PubMed

    Ngalame, Ntube N O; Tokar, Erik J; Person, Rachel J; Waalkes, Michael P

    2014-12-01

    Inorganic arsenic is a human carcinogen that likely targets the prostate. Chronic arsenic exposure malignantly transforms the RWPE-1 human prostate epithelial line to chronic arsenic exposed-prostate epithelial (CAsE-PE) cells, and a derivative normal prostate stem cell (SC) line, WPE-stem to arsenic-cancer SCs (As-CSCs). The KRAS oncogene is highly overexpressed in CAsE-PE cells and activation precedes transformation, inferring mechanistic significance. As-CSCs also highly overexpress KRAS. Thus, we hypothesize KRAS activation is key in causing and maintaining an arsenic-induced malignant phenotype, and hence, KRAS knockdown (KD) may reverse this malignant phenotype. RNA interference using shRNAmirs to obtain KRAS KD was used in CAsE-PE and As-CSC cells. Cells analyzed 2 weeks post transduction showed KRAS protein decreased to 5% of control after KD, confirming stable KD. KRAS KD decreased phosphorylated ERK, indicating inhibition of RAS/ERK signaling, a proliferation/survival pathway activated with arsenic transformation. Secreted metalloproteinase (MMP) activity was increased by arsenic-induced malignant transformation, but KRAS KD from 4 weeks on decreased secreted MMP-9 activity by 50% in As-CSCs. Colony formation, a characteristic of cancer cells, was decreased in both KRAS KD transformants. KRAS KD also decreased the invasive capacity of both cell types. KRAS KD decreased proliferation in As-CSCs, consistent with loss of rapid tumor growth. Genes predicted to impact cell proliferation (eg, Cyclin D1, p16, and p21) changed accordingly in both KD cell types. Thus, KRAS silencing impacts aspects of arsenic-induced malignant phenotype, inducing loss of many typical cancer characteristics particularly in As-CSCs.

  7. Overexpressed human heme Oxygenase-1 decreases adipogenesis in pigs and porcine adipose-derived stem cells.

    PubMed

    Park, Eun Jung; Koo, Ok Jae; Lee, Byeong Chun

    2015-11-27

    Adipose-derived mesenchymal stem cells (ADSC) are multipotent, which means they are able to differentiate into several lineages in vivo and in vitro under proper conditions. This indicates it is possible to determine the direction of differentiation of ADSC by controlling the microenvironment. Heme oxygenase 1 (HO-1), a type of antioxidant enzyme, attenuates adipogenicity and obesity. We produced transgenic pigs overexpressing human HO-1 (hHO-1-Tg), and found that these animals have little fatty tissue when autopsied. To determine whether overexpressed human HO-1 suppresses adipogenesis in pigs, we analyzed body weight increases of hHO-1-Tg pigs and wild type (WT) pigs of the same strain, and induced adipogenic differentiation of ADSC derived from WT and hHO-1-Tg pigs. The hHO-1-Tg pigs had lower body weights than WT pigs from 16 weeks of age until they died. In addition, hHO-1-Tg ADSC showed reduced adipogenic differentiation and expression of adipogenic molecular markers such as PPARγ and C/EBPα compared to WT ADSC. These results suggest that HO-1 overexpression reduces adipogenesis both in vivo and in vitro, which could support identification of therapeutic targets of obesity and related metabolic diseases.

  8. Human Neural Stem Cells Overexpressing Choline Acetyltransferase Restore Unconditioned Fear in Rats with Amygdala Injury

    PubMed Central

    Shin, Kyungha; Cha, Yeseul; Kim, Kwang Sei; Choi, Ehn-Kyoung; Choi, Youngjin; Guo, Haiyu; Ban, Young-Hwan; Kim, Jong-Choon; Park, Dongsun; Kim, Yun-Bae

    2016-01-01

    Amygdala is involved in the fear memory that recognizes certain environmental cues predicting threatening events. Manipulation of neurotransmission within the amygdala affects the expression of conditioned and unconditioned emotional memories such as fear freezing behaviour. We previously demonstrated that F3.ChAT human neural stem cells (NSCs) overexpressing choline acetyltransferase (ChAT) improve cognitive function of Alzheimer's disease model rats with hippocampal or cholinergic nerve injuries by increasing acetylcholine (ACh) level. In the present study, we examined the effect of F3.ChAT cells on the deficit of unconditioned fear freezing. Rats given N-methyl-d-aspartate (NMDA) in their amygdala 2 weeks prior to cat odor exposure displayed very short resting (freezing) time compared to normal animals. NMDA induced neuronal degeneration in the amygdala, leading to a decreased ACh concentration in cerebrospinal fluid. However, intracerebroventricular transplantation of F3.ChAT cells attenuated amygdala lesions 4 weeks after transplantation. The transplanted cells were found in the NMDA-injury sites and produced ChAT protein. In addition, F3.ChAT-receiving rats recuperated freezing time staying remote from the cat odor source, according to the recovery of brain ACh concentration. The results indicate that human NSCs overexpressing ChAT may facilitate retrieval of unconditioned fear memory by increasing ACh level. PMID:27087745

  9. Human Neural Stem Cells Overexpressing Choline Acetyltransferase Restore Unconditioned Fear in Rats with Amygdala Injury.

    PubMed

    Shin, Kyungha; Cha, Yeseul; Kim, Kwang Sei; Choi, Ehn-Kyoung; Choi, Youngjin; Guo, Haiyu; Ban, Young-Hwan; Kim, Jong-Choon; Park, Dongsun; Kim, Yun-Bae

    2016-01-01

    Amygdala is involved in the fear memory that recognizes certain environmental cues predicting threatening events. Manipulation of neurotransmission within the amygdala affects the expression of conditioned and unconditioned emotional memories such as fear freezing behaviour. We previously demonstrated that F3.ChAT human neural stem cells (NSCs) overexpressing choline acetyltransferase (ChAT) improve cognitive function of Alzheimer's disease model rats with hippocampal or cholinergic nerve injuries by increasing acetylcholine (ACh) level. In the present study, we examined the effect of F3.ChAT cells on the deficit of unconditioned fear freezing. Rats given N-methyl-d-aspartate (NMDA) in their amygdala 2 weeks prior to cat odor exposure displayed very short resting (freezing) time compared to normal animals. NMDA induced neuronal degeneration in the amygdala, leading to a decreased ACh concentration in cerebrospinal fluid. However, intracerebroventricular transplantation of F3.ChAT cells attenuated amygdala lesions 4 weeks after transplantation. The transplanted cells were found in the NMDA-injury sites and produced ChAT protein. In addition, F3.ChAT-receiving rats recuperated freezing time staying remote from the cat odor source, according to the recovery of brain ACh concentration. The results indicate that human NSCs overexpressing ChAT may facilitate retrieval of unconditioned fear memory by increasing ACh level. PMID:27087745

  10. The modeling of Alzheimer's disease by the overexpression of mutant Presenilin 1 in human embryonic stem cells.

    PubMed

    Honda, Makoto; Minami, Itsunari; Tooi, Norie; Morone, Nobuhiro; Nishioka, Hisae; Uemura, Kengo; Kinoshita, Ayae; Heuser, John E; Nakatsuji, Norio; Aiba, Kazuhiro

    2016-01-15

    Cellular disease models are useful tools for Alzheimer's disease (AD) research. Pluripotent stem cells, including human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs), are promising materials for creating cellular models of such diseases. In the present study, we established cellular models of AD in hESCs that overexpressed the mutant Presenilin 1 (PS1) gene with the use of a site-specific gene integration system. The overexpression of PS1 did not affect the undifferentiated status or the neural differentiation ability of the hESCs. We found increases in the ratios of amyloid-β 42 (Aβ42)/Aβ40 and Aβ43/Aβ40. Furthermore, synaptic dysfunction was observed in a cellular model of AD that overexpressed mutant PS1. These results suggest that the AD phenotypes, in particular, the electrophysiological abnormality of the synapses in our AD models might be useful for AD research and drug discovery.

  11. SIRT1 Overexpression Maintains Cell Phenotype and Function of Endothelial Cells Derived from Induced Pluripotent Stem Cells.

    PubMed

    Jiang, Bin; Jen, Michele; Perrin, Louisiane; Wertheim, Jason A; Ameer, Guillermo A

    2015-12-01

    Endothelial cells (ECs) that are differentiated from induced pluripotent stem cells (iPSCs) can be used in establishing disease models for personalized drug discovery or developing patient-specific vascularized tissues or organoids. However, a number of technical challenges are often associated with iPSC-ECs in culture, including instability of the endothelial phenotype and limited cell proliferative capacity over time. Early senescence is believed to be the primary mechanism underlying these limitations. Sirtuin1 (SIRT1) is an NAD(+)-dependent deacetylase involved in the regulation of cell senescence, redox state, and inflammatory status. We hypothesize that overexpression of the SIRT1 gene in iPSC-ECs will maintain EC phenotype, function, and proliferative capacity by overcoming early cell senescence. SIRT1 gene was packaged into a lentiviral vector (LV-SIRT1) and transduced into iPSC-ECs at passage 4. Beginning with passage 5, iPSC-ECs exhibited a fibroblast-like morphology, whereas iPSC-ECs overexpressing SIRT1 maintained EC cobblestone morphology. SIRT1 overexpressing iPSC-ECs also exhibited a higher percentage of canonical markers of endothelia (LV-SIRT1 61.8% CD31(+) vs. LV-empty 31.7% CD31(+), P < 0.001; LV-SIRT1 46.3% CD144(+) vs. LV-empty 20.5% CD144(+), P < 0.02), with a higher nitric oxide synthesis, lower β-galactosidase production indicating decreased senescence (3.4% for LV-SIRT1 vs. 38.6% for LV-empty, P < 0.001), enhanced angiogenesis, increased deacetylation activity, and higher proliferation rate. SIRT1 overexpressing iPSC-ECs continued to proliferate through passage 9 with high purity of EC-like characteristics, while iPSC-ECs without SIRT1 overexpression became senescent after passage 5. Taken together, SIRT1 overexpression in iPSC-ECs maintains EC phenotype, improves EC function, and extends cell lifespan, overcoming critical hurdles associated with the use of iPSC-ECs in translational research.

  12. Adenoviral overexpression of Lhx2 attenuates cell viability but does not preserve the stem cell like phenotype of hepatic stellate cells

    SciTech Connect

    Genz, Berit; Thomas, Maria; Pützer, Brigitte M.; Siatkowski, Marcin; Fuellen, Georg; Vollmar, Brigitte; Abshagen, Kerstin

    2014-11-01

    Hepatic stellate cells (HSC) are well known initiators of hepatic fibrosis. After liver cell damage, HSC transdifferentiate into proliferative myofibroblasts, representing the major source of extracellular matrix in the fibrotic organ. Recent studies also demonstrate a role of HSC as progenitor or stem cell like cells in liver regeneration. Lhx2 is described as stem cell maintaining factor in different organs and as an inhibitory transcription factor in HSC activation. Here we examined whether a continuous expression of Lhx2 in HSC could attenuate their activation and whether Lhx2 could serve as a potential target for antifibrotic gene therapy. Therefore, we evaluated an adenoviral mediated overexpression of Lhx2 in primary HSC and investigated mRNA expression patterns by qRT-PCR as well as the activation status by different in vitro assays. HSC revealed a marked increase in activation markers like smooth muscle actin alpha (αSMA) and collagen 1α independent from adenoviral transduction. Lhx2 overexpression resulted in attenuated cell viability as shown by a slightly hampered migratory and contractile phenotype of HSC. Expression of stem cell factors or signaling components was also unaffected by Lhx2. Summarizing these results, we found no antifibrotic or stem cell maintaining effect of Lhx2 overexpression in primary HSC. - Highlights: • We performed adenoviral overexpression of Lhx2 in primary hepatic stellate cells. • Hepatic stellate cells expressed stem cell markers during cultivation. • Cell migration and contractility was slightly hampered upon Lhx2 overexpression. • Lhx2 overexpression did not affect stem cell character of hepatic stellate cells.

  13. Preclinical evaluation of mesenchymal stem cells overexpressing VEGF to treat critical limb ischemia

    PubMed Central

    Beegle, Julie R; Magner, Nataly Lessa; Kalomoiris, Stefanos; Harding, Aja; Zhou, Ping; Nacey, Catherine; White, Jeannine Logan; Pepper, Karen; Gruenloh, William; Annett, Geralyn; Nolta, Jan A; Fierro, Fernando A

    2016-01-01

    Numerous clinical trials are utilizing mesenchymal stem cells (MSC) to treat critical limb ischemia, primarily for their ability to secrete signals that promote revascularization. These cells have demonstrated clinical safety, but their efficacy has been limited, possibly because these paracrine signals are secreted at subtherapeutic levels. In these studies the combination of cell and gene therapy was evaluated by engineering MSC with a lentivirus to overexpress vascular endothelial growth factor (VEGF). To achieve clinical compliance, the number of viral insertions was limited to 1–2 copies/cell and a constitutive promoter with demonstrated clinical safety was used. MSC/VEGF showed statistically significant increases in blood flow restoration as compared with sham controls, and more consistent improvements as compared with nontransduced MSC. Safety of MSC/VEGF was assessed in terms of genomic stability, rule-out tumorigenicity, and absence of edema or hemangiomas in vivo. In terms of retention, injected MSC/VEGF showed a steady decline over time, with a very small fraction of MSC/VEGF remaining for up to 4.5 months. Additional safety studies completed include absence of replication competent lentivirus, sterility tests, and absence of VSV-G viral envelope coding plasmid. These preclinical studies are directed toward a planned phase 1 clinical trial to treat critical limb ischemia.

  14. Preclinical evaluation of mesenchymal stem cells overexpressing VEGF to treat critical limb ischemia.

    PubMed

    Beegle, Julie R; Magner, Nataly Lessa; Kalomoiris, Stefanos; Harding, Aja; Zhou, Ping; Nacey, Catherine; White, Jeannine Logan; Pepper, Karen; Gruenloh, William; Annett, Geralyn; Nolta, Jan A; Fierro, Fernando A

    2016-01-01

    Numerous clinical trials are utilizing mesenchymal stem cells (MSC) to treat critical limb ischemia, primarily for their ability to secrete signals that promote revascularization. These cells have demonstrated clinical safety, but their efficacy has been limited, possibly because these paracrine signals are secreted at subtherapeutic levels. In these studies the combination of cell and gene therapy was evaluated by engineering MSC with a lentivirus to overexpress vascular endothelial growth factor (VEGF). To achieve clinical compliance, the number of viral insertions was limited to 1-2 copies/cell and a constitutive promoter with demonstrated clinical safety was used. MSC/VEGF showed statistically significant increases in blood flow restoration as compared with sham controls, and more consistent improvements as compared with nontransduced MSC. Safety of MSC/VEGF was assessed in terms of genomic stability, rule-out tumorigenicity, and absence of edema or hemangiomas in vivo. In terms of retention, injected MSC/VEGF showed a steady decline over time, with a very small fraction of MSC/VEGF remaining for up to 4.5 months. Additional safety studies completed include absence of replication competent lentivirus, sterility tests, and absence of VSV-G viral envelope coding plasmid. These preclinical studies are directed toward a planned phase 1 clinical trial to treat critical limb ischemia. PMID:27610394

  15. Preclinical evaluation of mesenchymal stem cells overexpressing VEGF to treat critical limb ischemia

    PubMed Central

    Beegle, Julie R; Magner, Nataly Lessa; Kalomoiris, Stefanos; Harding, Aja; Zhou, Ping; Nacey, Catherine; White, Jeannine Logan; Pepper, Karen; Gruenloh, William; Annett, Geralyn; Nolta, Jan A; Fierro, Fernando A

    2016-01-01

    Numerous clinical trials are utilizing mesenchymal stem cells (MSC) to treat critical limb ischemia, primarily for their ability to secrete signals that promote revascularization. These cells have demonstrated clinical safety, but their efficacy has been limited, possibly because these paracrine signals are secreted at subtherapeutic levels. In these studies the combination of cell and gene therapy was evaluated by engineering MSC with a lentivirus to overexpress vascular endothelial growth factor (VEGF). To achieve clinical compliance, the number of viral insertions was limited to 1–2 copies/cell and a constitutive promoter with demonstrated clinical safety was used. MSC/VEGF showed statistically significant increases in blood flow restoration as compared with sham controls, and more consistent improvements as compared with nontransduced MSC. Safety of MSC/VEGF was assessed in terms of genomic stability, rule-out tumorigenicity, and absence of edema or hemangiomas in vivo. In terms of retention, injected MSC/VEGF showed a steady decline over time, with a very small fraction of MSC/VEGF remaining for up to 4.5 months. Additional safety studies completed include absence of replication competent lentivirus, sterility tests, and absence of VSV-G viral envelope coding plasmid. These preclinical studies are directed toward a planned phase 1 clinical trial to treat critical limb ischemia. PMID:27610394

  16. Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 undergo the stochastic cardiomyogenic fate and behave like transient amplifying cells

    SciTech Connect

    Yamada, Yoji; Sakurada, Kazuhiro; Takeda, Yukiji; Gojo, Satoshi; Umezawa, Akihiro . E-mail: umezawa@1985.jukuin.keio.ac.jp

    2007-02-15

    Bone marrow-derived stromal cells can give rise to cardiomyocytes as well as adipocytes, osteocytes, and chondrocytes in vitro. The existence of mesenchymal stem cells has been proposed, but it remains unclear if a single-cell-derived stem cell stochastically commits toward a cardiac lineage. By single-cell marking, we performed a follow-up study of individual cells during the differentiation of 9-15c mesenchymal stromal cells derived from bone marrow cells. Three types of cells, i.e., cardiac myoblasts, cardiac progenitors and multipotent stem cells were differentiated from a single cell, implying that cardiomyocytes are generated stochastically from a single-cell-derived stem cell. We also demonstrated that overexpression of Csx/Nkx2.5 and GATA4, precardiac mesodermal transcription factors, enhanced cardiomyogenic differentiation of 9-15c cells, and the frequency of cardiomyogenic differentiation was increased by co-culturing with fetal cardiomyocytes. Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 behaved like cardiac transient amplifying cells, and still retained their plasticity in vivo.

  17. Overexpression of FABP3 inhibits human bone marrow derived mesenchymal stem cell proliferation but enhances their survival in hypoxia

    SciTech Connect

    Wang, Suna Zhou, Yifu; Andreyev, Oleg; Hoyt, Robert F.; Singh, Avneesh; Hunt, Timothy; Horvath, Keith A.

    2014-04-15

    Studying the proliferative ability of human bone marrow derived mesenchymal stem cells in hypoxic conditions can help us achieve the effective regeneration of ischemic injured myocardium. Cardiac-type fatty acid binding protein (FABP3) is a specific biomarker of muscle and heart tissue injury. This protein is purported to be involved in early myocardial development, adult myocardial tissue repair and responsible for the modulation of cell growth and proliferation. We have investigated the role of FABP3 in human bone marrow derived mesenchymal stem cells under ischemic conditions. MSCs from 12 donors were cultured either in standard normoxic or modified hypoxic conditions, and the differential expression of FABP3 was tested by quantitative {sup RT}PCR and western blot. We also established stable FABP3 expression in MSCs and searched for variation in cellular proliferation and differentiation bioprocesses affected by hypoxic conditions. We identified: (1) the FABP3 differential expression pattern in the MSCs under hypoxic conditions; (2) over-expression of FABP3 inhibited the growth and proliferation of the MSCs; however, improved their survival in low oxygen environments; (3) the cell growth factors and positive cell cycle regulation genes, such as PCNA, APC, CCNB1, CCNB2 and CDC6 were all down-regulated; while the key negative cell cycle regulation genes TP53, BRCA1, CASP3 and CDKN1A were significantly up-regulated in the cells with FABP3 overexpression. Our data suggested that FABP3 was up-regulated under hypoxia; also negatively regulated the cell metabolic process and the mitotic cell cycle. Overexpression of FABP3 inhibited cell growth and proliferation via negative regulation of the cell cycle and down-regulation of cell growth factors, but enhances cell survival in hypoxic or ischemic conditions. - Highlights: • FABP3 expression pattern was studied in 12 human hypoxic-MSCs. • FABP3 mRNA and proteins are upregulated in the MSCs under hypoxic conditions.

  18. Engineered hair follicle mesenchymal stem cells overexpressing controlled-release insulin reverse hyperglycemia in mice with type L diabetes.

    PubMed

    Wu, Chunling; Liu, Feilin; Li, Pengdong; Zhao, Guifang; Lan, Shaowei; Jiang, Wenyue; Meng, Xiangwei; Tian, Lixing; Li, Gang; Li, Yulin; Liu, Jin Yu

    2015-01-01

    Genetically engineered stem cells that overexpress genes encoding therapeutic products can be exploited to correct metabolic disorders by repairing and regenerating diseased organs or restoring their function. Hair follicles are readily accessible and serve as a rich source of autologous stem cells for cell-based gene therapy. Here we isolated mesenchymal stem cells from human hair follicles (HF-MSCs) and engineered them to overexpress the human insulin gene and release human insulin in a time- and dose-dependent manner in response to rapamycin. The engineered HF-MSCs retained their characteristic cell surface markers and retained their potential to differentiate into adipocytes and osteoblasts. When mice with streptozotocin-induced type 1 diabetes were engrafted with these engineered HF-MSCs, these cells expressed and released a dose of human insulin, dramatically reversed hyperglycemia, and significantly reduced death rate. Moreover, the engineered HF-MSCs did not form detectable tumors throughout the 120-day animal tests in our experiment. Our results show that HF-MSCs can be used to safely and efficiently express therapeutic transgenes and therefore show promise for cell-based gene therapy of human disease.

  19. Overexpression of TGF-β1 enhances chondrogenic differentiation and proliferation of human synovium-derived stem cells

    SciTech Connect

    Kim, Yong Il; Ryu, Jae-Sung; Yeo, Jee Eun; Choi, Yun Jin; Kim, Yong Sang; Ko, Kinarm; Koh, Yong-Gon

    2014-08-08

    Highlights: • Continuous TGF-β1 overexpression in hSD-MSCs did not influence their phenotypes. • Retroviral-mediated transduction of TGFB1 in hSD-MSCs enhances cell proliferation. • TGF-β1 overexpression did not effect to adipo- or osteogenic potential of hSD-MSCs. • TGF-β1 overexpression in hSD-MSCs could stimulate and accelerate chondrogenesis. - Abstract: Transforming growth factor-beta (TGF-β) superfamily proteins play a critical role in proliferation, differentiation, and other functions of mesenchymal stem cells (MSCs). During chondrogenic differentiation of MSCs, TGF-β up-regulates chondrogenic gene expression by enhancing the expression of the transcription factor SRY (sex-determining region Y)-box9 (Sox9). In this study, we investigated the effect of continuous TGF-β1 overexpression in human synovium-derived MSCs (hSD-MSCs) on immunophenotype, differentiation potential, and proliferation rate. hSD-MSCs were transduced with recombinant retroviruses (rRV) encoding TGF-β1. The results revealed that continuous overexpression of TGF-β1 did not affect their phenotype as evidenced by flow cytometry and reverse transcriptase PCR (RT-PCR). In addition, continuous TGF-β1 overexpression strongly enhanced cell proliferation of hSD-MSCs compared to the control groups. Also, induction of chondrogenesis was more effective in rRV-TGFB-transduced hSD-MSCs as shown by RT-PCR for chondrogenic markers, toluidine blue staining and glycosaminoglycan (GAG)/DNA ratio. Our data suggest that overexpression of TGF-β1 positively enhances the proliferation and chondrogenic potential of hSD-MSCs.

  20. Oct4 and Sox2 overexpression improves the proliferation and differentiation of bone mesenchymal stem cells in Xiaomeishan porcine.

    PubMed

    Fan, Y X; Gu, C H; Zhang, Y L; Zhong, B S; Wang, L Z; Zhou, Z R; Wang, Z Y; Jia, R X; Wang, F

    2013-01-01

    Mesenchymal stem cells derived from bone marrow (BMSCs) are a population of self-renewing multipotent cells that are capable of differentiating into various cellular lineages, and are widely employed in tissue engineering and cell therapy. Recently, clinical research involving BMSCs has become increasingly popular. In order to conduct appropriate research, it is first necessary to amplify large amounts of functional BMSCs in vitro. However, after several passages of expanding in vitro, the proliferation and differentiation potential of BMSCs gradually decline. To determine whether overexpression of Oct4 or Sox2 might prevent this decline, we transfected Oct4 or Sox2, which are essential for the pluripotency and self-renewal of embryonic stem cells, into BMSCs of Xiaomeishan porcine by a lentivirus. The results showed that overexpression of Sox2 or Oct4 BMSCs in culture media containing a basic fibroblast growth factor resulted in higher proliferation and differentiation compared to controls, suggesting that genetic modification of stemness-related genes is an efficient way to maintain the proliferation and differentiation potential of BMSCs. PMID:24338401

  1. Adenovirus-Mediated Over-Expression of Nrf2 Within Mesenchymal Stem Cells (MSCs) Protected Rats Against Acute Kidney Injury

    PubMed Central

    Mohammadzadeh-Vardin, Mohammad; Habibi Roudkenar, Mehryar; Jahanian-Najafabadi, Ali

    2015-01-01

    Purpose: Recent developments in the field of cell therapy have led to a renewed interest in treatment of acute kidney injury (AKI). However, the early death of transplanted mesenchymal stem cells (MSCs) in stressful microenvironment of a recipient tissue is a major problem with this kind of treatment. The objective of this study was to determine whether overexpression of a cytoprotective factor, nuclear factor erythroid-2 related factor 2 (Nrf2), in MSCs could protect rats against AKI. Methods: The Nrf2 was overexpressed in MSCs by recombinant adenoviruses, and the MSCs were implanted to rats suffering from cisplatin-induced AKI. Results: The obtained results showed that transplantation with the engineered MSCs ameliorates cisplatin-induced AKI. Morphologic features of the investigated kidneys showed that transplantation with the MSCs in which Nrf2 had been overexpressed significantly improved the complications of AKI. Conclusion: These findings suggested that the engineered MSCs might be a good candidate to be further evaluated in clinical trials. However, detailed studies must be performed to investigate the possible carcinogenic effect of Nrf2 overexpression. PMID:26236658

  2. Overexpression of protein kinase C ɛ improves retention and survival of transplanted mesenchymal stem cells in rat acute myocardial infarction

    PubMed Central

    He, H; Zhao, Z-H; Han, F-S; Liu, X-H; Wang, R; Zeng, Y-J

    2016-01-01

    We assessed the effects of protein kinase C ɛ (PKCɛ) for improving stem cell therapy for acute myocardial infarction (AMI). Primary mesenchymal stem cells (MSCs) were harvested from rat bone marrow. PKCɛ-overexpressed MSCs and control MSCs were transplanted into infarct border zones in a rat AMI model. MSCs and PKCɛ distribution and expression of principal proteins involved in PKCɛ signaling through the stromal cell-derived factor 1 (SDF-1)/CXC chemokine receptor type 4 (CXCR4) axis and the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT) pathway were analyzed by immunofluorescence and western blot 1 day after transplantation. Echocardiographic measurements and histologic studies were performed at 4 weeks after transplantation, and MSC survival, expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor β (TGFβ), cardiac troponin I (cTnI), von Willebrand factor (vWF), smooth muscle actin (SMA) and factor VIII and apoptosis in infarct border zones were assessed. Rat heart muscles retained more MSCs and SDF-1, CXCR4, PI3K and phosphorylated AKT increased with PKCɛ overexpression 1 day after transplantation. MSC survival and VEGF, bFGF, TGFβ, cTnI, vWF, SMA and factor VIII expression increased in animals with PKCɛ-overexpressed MSCs at 4 weeks after transplantation and cardiac dysfunction and remodeling improved. Infarct size and apoptosis decreased as well. Inhibitory actions of CXCR4 or PI3K partly attenuated the effects of PKCɛ. Activation of PKCɛ may improve retention, survival and differentiation of transplanted MSCs in myocardia. Augmentation of PKCɛ expression may enhance the therapeutic effects of stem cell therapy for AMI. PMID:26775707

  3. Polymer-DNA Nanoparticle-Induced CXCR4 Overexpression Improves Stem Cell Engraftment and Tissue Regeneration in a Mouse Hindlimb Ischemia Model

    PubMed Central

    Deveza, Lorenzo; Choi, Jeffrey; Lee, Jerry; Huang, Ngan; Cooke, John; Yang, Fan

    2016-01-01

    Peripheral arterial disease affects nearly 202 million individuals worldwide, sometimes leading to non-healing ulcers or limb amputations in severe cases. Genetically modified stem cells offer potential advantages for therapeutically inducing angiogenesis via augmented paracrine release mechanisms and tuned dynamic responses to environmental stimuli at disease sites. Here, we report the application of nanoparticle-induced CXCR4-overexpressing stem cells in a mouse hindlimb ischemia model. We found that CXCR4 overexpression improved stem cell survival, modulated inflammation in situ, and accelerated blood reperfusion. These effects, unexpectedly, led to complete limb salvage and skeletal muscle repair, markedly outperforming the efficacy of the conventional angiogenic factor control, VEGF. Importantly, assessment of CXCR4-overexpressing stem cells in vitro revealed that CXCR4 overexpression induced changes in paracrine signaling of stem cells, promoting a therapeutically desirable pro-angiogenic and anti-inflammatory phenotype. These results suggest that nanoparticle-induced CXCR4 overexpression may promote favorable phenotypic changes and therapeutic efficacy of stem cells in response to the ischemic environment. PMID:27279910

  4. Mesenchymal stem cells with Sirt1 overexpression suppress breast tumor growth via chemokine-dependent natural killer cells recruitment

    PubMed Central

    Yu, Yang; Liu, Yan; Zong, Chen; Yu, Qingbo; Yang, Xue; Liang, Lei; Ye, Fei; Nong, Li; Jia, Yuxian; Lu, Yongkui; Han, Zhipeng

    2016-01-01

    Mesenchymal stem cells (MSCs) are generally used in regenerative medicine, tissue engineering and therapy for immune disorder diseases. However, due to the immunosuppressive function of MSCs, the application of MSCs in breast cancer therapy remains limited. Sirt1 is the closest mammalian homologue of the yeast enzyme Sir2 which has an established capacity to influence yeast replicative lifespan. In this study, we demonstrated the effect of MSCs with Sirt1 overexpression (MSCs-Sirt1) in mice bearing 4T1 breast cancer and investigated the underlying mechanism. Firstly, we found that MSCs could accelerate breast tumor growth with promoted proliferation and inhibited apoptosis, whereas MSCs-Sirt1 significantly suppressed tumor growth with proliferation inhibition and apoptosis promotion. Moreover, we detected that NK cells were the prominent antitumor effectors for the MSCs-Sirt1-induced antitumor activity. Besides that, CXCL10 and IFN-γ showed the high level expression in MSCs-Sirt1 treatment group. The impulsive effect of MSCs-Sirt1 on 4T1 cells in vivo could be reversed by inhibition of CXCL10 and IFN-γ. Overall, our results suggest that MSCs-Sirt1 can effectively inhibit breast tumor growth via the recruitment of NK cells in tumor inflammatory microenvironment. PMID:27782173

  5. Stemness and chemotherapeutic drug resistance induced by EIF5A2 overexpression in esophageal squamous cell carcinoma.

    PubMed

    Yang, Hong; Li, Xiao-dong; Zhou, Ying; Ban, Xiaojiao; Zeng, Ting-ting; Li, Lei; Zhang, Bao-zhu; Yun, Jingping; Xie, Dan; Guan, Xin-Yuan; Li, Yan

    2015-09-22

    Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies of the digestive tract in East Asian countries. Multimodal therapies, including adjuvant chemotherapy and neo-adjuvant chemotherapy, have become more often used for patients with advanced ESCC. However, the chemotherapy effect is often limited by patients' drug resistance. This study demonstrated that EIF5A2 (eukaryotic translation initiation factor 5A2) overexpression induced stemness and chemoresistance in ESCC cells. We showed that EIF5A2 overexpression in ESCC cells resulted in increased chemoresistance to 5-fluorouracil (5-FU), docetaxel and taxol. In contrast, shRNAs suppressing eIF5A2 increased tumor sensitivity to these chemotherapeutic drugs. In addition, EIF5A2 overexpression was correlated with a poorer overall survival in patients with ESCC who underwent taxane-based chemotherapy after esophagectomy (P < 0.05). Based on these results, we suggest that EIF5A2 could be a predictive biomarker for selecting appropriate chemo-treatment for ESCC patients and EIF5A2 inhibitors might be considered as combination therapy to enhance chemosensitivity in patients with ESCC.

  6. Poly(ADP-Ribose) Polymerase 1 (PARP1) Overexpression in Human Breast Cancer Stem Cells and Resistance to Olaparib

    PubMed Central

    Ginestier, Christophe; Bertucci, François; Audebert, Stéphane; Pophillat, Mathieu; Toiron, Yves; Baudelet, Emilie; Finetti, Pascal; Noguchi, Tetsuro; Sobol, Hagay; Birnbaum, Daniel; Borg, Jean-Paul; Charafe-Jauffret, Emmanuelle; Gonçalves, Anthony

    2014-01-01

    Background Breast cancer stem cells (BCSCs) have been recognized as playing a major role in various aspects of breast cancer biology. To identify specific biomarkers of BCSCs, we have performed comparative proteomics of BCSC-enriched and mature cancer cell populations from the human breast cancer cell line (BCL), BrCA-MZ-01. Methods ALDEFLUOR assay was used to sort BCSC-enriched (ALDH+) and mature cancer (ALDH−) cell populations. Total proteins were extracted from both fractions and subjected to 2-Dimensional Difference In-Gel Electrophoresis (2-D DIGE). Differentially-expressed spots were excised and proteins were gel-extracted, digested and identified using MALDI-TOF MS. Results 2-D DIGE identified poly(ADP-ribose) polymerase 1 (PARP1) as overexpressed in ALDH+ cells from BrCA-MZ-01. This observation was confirmed by western blot and extended to four additional human BCLs. ALDH+ cells from BRCA1-mutated HCC1937, which had the highest level of PARP1 overexpression, displayed resistance to olaparib, a specific PARP1 inhibitor. Conclusion An unbiased proteomic approach identified PARP1 as upregulated in ALDH+, BCSC-enriched cells from various human BCLs, which may contribute to clinical resistance to PARP inhibitors. PMID:25144364

  7. Directing cardiomyogenic differentiation of human pluripotent stem cells by plasmid-based transient overexpression of cardiac transcription factors.

    PubMed

    Hartung, Susann; Schwanke, Kristin; Haase, Alexandra; David, Robert; Franz, Wolfgang-Michael; Martin, Ulrich; Zweigerdt, Robert

    2013-04-01

    Cardiomyocytes (CMs) derived from human pluripotent stem cells (hPSCs) possess a high potential for regenerative medicine. Previous publications suggested that viral transduction of a defined set of transcription factors (TFs) known to play pivotal roles in heart development also increases cardiomyogenesis in vitro upon overexpression in mouse or human ES cells. To circumvent issues associated with viral approaches such as insertional mutagenesis, we have established a transient transfection system for straightforward testing of TF combinations. Applying this method, the transfection efficiency and the temporal pattern of transgene expression were extensively assessed in hPSCs by quantitative real time-polymerase chain reaction (qRT-PCR), TF-specific immunofluorescence analysis, and flow cytometry. Testing TF combinations in our approach revealed that BAF60C, GATA4, and MESP1 (BGM) were most effective for cardiac forward programming in human induced pluripotent stem cell lines and human ES cells as well. Removal of BAF60C slightly diminished formation of CM-like cells, whereas depletion of GATA4 or MESP1 abolished cardiomyogenesis. Each of these TFs alone had no inductive effect. In addition, we have noted sensitivity of CM formation to cell density effects, which highlights the necessity for cautious analysis when interpreting TF-directed lineage induction. In summary, this is the first report on TF-induced cardiomyogenesis of hPSCs applying a transient, nonintegrating method of cell transfection.

  8. 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 ...

  9. 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

  10. Stromal cell-derived factor-1 receptor CXCR4-overexpressing bone marrow mesenchymal stem cells accelerate wound healing by migrating into skin injury areas.

    PubMed

    Yang, Dazhi; Sun, Shijin; Wang, Zhengguo; Zhu, Peifang; Yang, Zailiang; Zhang, Bo

    2013-06-01

    Stromal cell-derived factor-1 (SDF-1) and its membrane receptor C-X-C chemokine receptor type 4 (CXCR4) are involved in the homing and migration of multiple stem cell types, neovascularization, and cell proliferation. This study investigated the hypothesis that bone marrow-derived mesenchymal stem cells (BMSCs) accelerate skin wound healing in the mouse model by overexpression of CXCR4 in BMSCs. We compared SDF-1 expression and skin wound healing times of BALB/c mice, severe combined immunodeficiency (SCID) mice, and immune system-deficient nude mice after (60)Co radiation-induced injury of their bone marrow. The occurrence of transplanted adenovirus-transfected CXCR4-overexpressing male BMSCs in the wound area was compared with the occurrence of untransfected male BALB/c BMSCs in (60)Co-irradiated female mice skin wound healing areas by Y chromosome marker analyses. The wound healing time of BALB/c mice was 14.00±1.41 days, whereas for the nude and SCID mice it was 17.16±1.17 days and 19.83±0.76 days, respectively. Male BMSCs could be detected in the surrounding areas of (60)Co-irradiated female BALB/c mice wounds, and CXCR4-overexpressing BMSCs accelerated the wound healing time. CXCR4-overexpressing BMSCs migrate in an enhanced manner to skin wounds in a SDF-1-expression-dependent manner, thereby reducing the skin wound healing time.

  11. Comparison of viability and antioxidant capacity between canine adipose-derived mesenchymal stem cells and heme oxygenase-1-overexpressed cells after freeze-thawing

    PubMed Central

    KIM, Mijung; KIM, Yongsun; LEE, Seunghoon; KUK, Minyoung; KIM, Ah Young; KIM, Wanhee; KWEON, Oh-Kyeong

    2015-01-01

    Allogenic adipose-derived mesenchymal stem cells (Ad-MSCs) are an alternative source for cytotherapy owing to their antioxidant and anti-inflammatory effects. Frozen-thawed allogenic Ad-MSCs can be used instantly for this purpose. However, the viability and function of frozen-thawed Ad-MSCs have not been clearly evaluated. The purpose of this study was to compare the viability and function of Ad-MSCs and heme oxygenase-1 (HO-1)-overexpressed Ad-MSCs in vitro after freeze-thawing. The viability, proliferation, antioxidant capacity and mRNA gene expression of growth factors were evaluated. Frozen-thawed cells showed significantly lower viability than fresh cells (77% for Ad-MSCs and 71% for HO-1 Ad-MSCs, P<0.01). However, the proliferation rate of frozen-thawed Ad-MSCs increased and did not differ from that of fresh Ad-MSCs after 3 days of culture. In contrast, the proliferation rate of HO-1-overexpressed Ad-MSCs was lower than that of Ad-MSCs. The mRNA expression levels of TGF-β, HGF and VEGF did not differ between fresh and frozen-thawed Ad-MSCs, but COX-2 and IL-6 had significantly higher mRNA expression in frozen cells than fresh cells (P<0.05). Fresh Ad-MSCs exhibited higher HO-1 mRNA expression than frozen-thawed Ad-MSCs, and fresh HO-1-overexpressed Ad-MSCs exhibited higher than fresh Ad-MSCs (P<0.05). However, there was no significant difference between fresh and frozen HO-1-overexpressed Ad-MSCs. The antioxidant capacity of HO-1-overexpressed Ad-MSCs was significantly higher than that of Ad-MSCs. Cryopreservation of Ad-MSCs negatively affects viability and antioxidant capacity, and HO-1-overexpressed Ad-MSCs might be useful to maximize the effect of Ad-MSCs for cytotherapy. PMID:26725542

  12. Nucleolin overexpression in breast cancer cell sub-populations with different stem-like phenotype enables targeted intracellular delivery of synergistic drug combination.

    PubMed

    Fonseca, Nuno A; Rodrigues, Ana S; Rodrigues-Santos, Paulo; Alves, Vera; Gregório, Ana C; Valério-Fernandes, Ângela; Gomes-da-Silva, Lígia C; Rosa, Manuel Santos; Moura, Vera; Ramalho-Santos, João; Simões, Sérgio; Moreira, João Nuno

    2015-11-01

    Breast cancer stem cells (CSC) are thought responsible for tumor growth and relapse, metastization and active evasion to standard chemotherapy. The recognition that CSC may originate from non-stem cancer cells (non-SCC) through plastic epithelial-to-mesenchymal transition turned these into relevant cell targets. Of crucial importance for successful therapeutic intervention is the identification of surface receptors overexpressed in both CSC and non-SCC. Cell surface nucleolin has been described as overexpressed in cancer cells as well as a tumor angiogenic marker. Herein we have addressed the questions on whether nucleolin was a common receptor among breast CSC and non-SCC and whether it could be exploited for targeting purposes. Liposomes functionalized with the nucleolin-binding F3 peptide, targeted simultaneously, nucleolin-overexpressing putative breast CSC and non-SCC, which was paralleled by OCT4 and NANOG mRNA levels in cells from triple negative breast cancer (TNBC) origin. In murine embryonic stem cells, both nucleolin mRNA levels and F3 peptide-targeted liposomes cellular association were dependent on the stemness status. An in vivo tumorigenic assay suggested that surface nucleolin overexpression per se, could be associated with the identification of highly tumorigenic TNBC cells. This proposed link between nucleolin expression and the stem-like phenotype in TNBC, enabled 100% cell death mediated by F3 peptide-targeted synergistic drug combination, suggesting the potential to abrogate the plasticity and adaptability associated with CSC and non-SCC. Ultimately, nucleolin-specific therapeutic tools capable of simultaneous debulk multiple cellular compartments of the tumor microenvironment may pave the way towards a specific treatment for TNBC patient care.

  13. Geminin overexpression-dependent recruitment and crosstalk with mesenchymal stem cells enhance aggressiveness in triple negative breast cancers

    PubMed Central

    Ananthula, Suryatheja; Sinha, Abhilasha; Gassim, Mohamed El; Batth, Simran; Marshall, Gailen D.; Gardner, Lauren H.; Shimizu, Yoshiko; ElShamy, Wael M.

    2016-01-01

    Resident mesenchymal stem cells (MSCs) promote cancer progression. However, pathways and mechanisms involved in recruiting MSCs into breast tumors remain largely undefined. Here we show that geminin-dependent acetylation releases HMGB1 from the chromatin to the cytoplasm and extracellular space. Extracellular acetylated HMGB1 (Ac-HMGB1) promotes geminin overexpressing (GemOE) cells survival by binding to RAGE and activating NF-κB signaling. Extracellular Ac-HMGB1 also triggers expression and activation of RAGE in the non-expressing MSCs. RAGE activation induces expression of CXCR4 in MSCs and directional migration towards SDF1 (aka CXCL12)-expressing GemOE cells in vitro and in vivo. These effects augmented by the necrotic and hypoxic environment in GemOE tumors, especially within their cores. Reciprocal interactions between newly recruited MSCs and GemOE tumor cells elevate tumor-initiating (TIC), basal and epithelial-to-mesenchymal transition (EMT) traits and enhance aggressiveness in vitro and in vivo in GemOE tumor cells. Indeed, faster, larger and more aggressive tumors develop when GemOE cells are co-injected with MSCs in orthotopic breast tumor model. Concurrently, inhibiting c-Abl (and thus geminin function), RAGE or CXCR4 prevented MSCs recruitment to GemOE cells in vitro and in vivo, and decreased the TIC, basal and EMT phenotypes in these tumor cells. Accordingly, we propose that GemOE tumor cells present within tumor cores represent metastatic precursors, and suppressing the GemOE→HMGB1/RAGE→SDF1/CXCR4 signaling circuit could be a valid target for therapies to inhibit GemOE tumors and their metastases. PMID:26989079

  14. Nilotinib enhances the efficacy of conventional chemotherapeutic drugs in CD34⁺CD38⁻ stem cells and ABC transporter overexpressing leukemia cells.

    PubMed

    Wang, Fang; Wang, Xiao-Kun; Shi, Cheng-Jun; Zhang, Hui; Hu, Ya-Peng; Chen, Yi-Fan; Fu, Li-Wu

    2014-03-19

    Incomplete chemotherapeutic eradication of leukemic CD34⁺CD38⁻ stem cells is likely to result in disease relapse. The purpose of this study was to evaluate the effect of nilotinib on eradicating leukemia stem cells and enhancing the efficacy of chemotherapeutic agents. Our results showed that ABCB1 and ABCG2 were preferentially expressed in leukemic CD34⁺CD38⁻ cells. Nilotinib significantly enhanced the cytotoxicity of doxorubicin and mitoxantrone in CD34⁺CD38⁻ cells and led to increased apoptosis. Moreover, nilotinib strongly reversed multidrug resistance and increased the intracellular accumulation of rhodamine 123 in primary leukemic blasts overexpressing ABCB1 and/or ABCG2. Studies with ABC transporter-overexpressing carcinoma cell models confirmed that nilotinib effectively reversed ABCB1- and ABCG2-mediated drug resistance, while showed no significant reversal effect on ABCC1- and ABCC4-mediated drug resistance. Results from cytotoxicity assays showed that CD34⁺CD38⁻ cells exhibited moderate resistance (2.41-fold) to nilotinib, compared with parental K562 cells. Furthermore, nilotinib was less effective in blocking the phosphorylation of Bcr-Abl and CrkL (a substrate of Bcr-Abl kinase) in CD34⁺CD38⁻ cells. Taken together, these data suggest that nilotinib particularly targets CD34⁺CD38⁻ stem cells and MDR leukemia cells, and effectively enhances the efficacy of chemotherapeutic drugs by blocking the efflux function of ABC transporters.

  15. Overexpression of HSPA1A enhances the osteogenic differentiation of bone marrow mesenchymal stem cells via activation of the Wnt/β-catenin signaling pathway

    PubMed Central

    Zhang, Wei; Xue, Deting; Yin, Houfa; Wang, Shengdong; Li, Chao; Chen, Erman; Hu, Dongcai; Tao, Yiqing; Yu, Jiawei; Zheng, Qiang; Gao, Xiang; Pan, Zhijun

    2016-01-01

    HSPA1A, which encodes cognate heat shock protein 70, plays important roles in various cellular metabolic pathways. To investigate its effects on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), its expression level was compared between undifferentiated and differentiated BMSCs. Rat HSPA1A overexpression in BMSCs increased osteoblast-specific gene expression, alkaline phosphatase activity, and mineral deposition in vitro. Moreover, it upregulated β-catenin and downregulated DKK1 and SOST. The enhanced osteogenesis due to HSPA1A overexpression was partly rescued by a Wnt/β-catenin inhibitor. Additionally, using a rat tibial fracture model, a sheet of HSPA1A-overexpressing BMSCs improved bone fracture healing, as determined by imaging and histological analysis. Taken together, these findings suggest that HSPA1A overexpression enhances osteogenic differentiation of BMSCs, partly through Wnt/β-catenin. PMID:27279016

  16. High throughput quantitative reverse transcription PCR assays revealing over-expression of cancer testis antigen genes in multiple myeloma stem cell-like side population cells.

    PubMed

    Wen, Jianguo; Li, Hangwen; Tao, Wenjing; Savoldo, Barbara; Foglesong, Jessica A; King, Lauren C; Zu, Youli; Chang, Chung-Che

    2014-09-01

    Multiple myeloma (MM) stem cells, proposed to be responsible for the tumourigenesis, drug resistance and recurrence of this disease, are enriched in the cancer stem cell-like side population (SP). Cancer testis antigens (CTA) are attractive targets for immunotherapy because they are widely expressed in cancers but only in limited types of normal tissues. We designed a high throughput assay, which allowed simultaneous relative quantifying expression of 90 CTA genes associated with MM. In the three MM cell lines tested, six CTA genes were over-expressed in two and LUZP4 and ODF1 were universally up-regulated in all three cell lines. Subsequent study of primary bone marrow (BM) from eight MM patients and four healthy donors revealed that 19 CTA genes were up-regulated in SP of MM compared with mature plasma cells. In contrast, only two CTA genes showed a moderate increase in SP cells of healthy BM. Furthermore, knockdown using small interfering RNA (siRNA) revealed that LUZP4 expression is required for colony-forming ability and drug resistance in MM cells. Our findings indicate that multiple CTA have unique expression profiles in MM SP, suggesting that CTA may serve as targets for immunotherapy that it specific for MM stem cells and which may lead to the long-term cure of MM.

  17. The effects of BMP6 overexpression on adipose stem cell chondrogenesis: Interactions with dexamethasone and exogenous growth factors.

    PubMed

    Diekman, Brian O; Estes, Bradley T; Guilak, Farshid

    2010-06-01

    Adipose-derived stem cells (ASCs) are multipotent progenitors that can be chondrogenically induced by growth factors such as bone morphogenetic protein 6 (BMP-6). We hypothesized that nonviral transfection of a BMP-6 construct (pcDNA3-BMP6) would induce chondrogenic differentiation of ASCs encapsulated in alginate beads and that differentiation would be enhanced by the presence of the synthetic glucocorticoid dexamethasone (DEX) or the combination of epidermal growth factor (EGF), fibroblast growth factor-2 (FGF-2), and transforming growth factor beta-1 (TGF-beta1), collectively termed expansion factors (EFs). Chondrogenesis was assessed using quantitative real-time polymerase chain reaction for types I, II, and X collagen, aggrecan, and BMP6. Immunohistochemistry was performed with antibodies for types I, II, and X collagen and chondroitin-4-sulfate. BMP6 overexpression alone induced a moderate chondrogenic response. The inclusion of EFs promoted robust type II collagen expression but also increased type I and X collagen deposition, consistent with a hypertrophic chondrocyte phenotype. Early gene expression data indicated that DEX was synergistic with BMP-6 for chondrogenesis, but immunohistochemistry at 28 days showed that DEX reduced glycosaminoglycan accumulation. These results suggest that chondrogenic differentiation of ASCs depends on complex interactions among various growth factors and media supplements, as well as the concentration and duration of growth factor exposure. PMID:19722282

  18. Genetic Modification of Mesenchymal Stem Cells Overexpressing CCR1 Increases Cell Viability, Migration, Engraftment and Capillary Density in the Injured Myocardium

    PubMed Central

    Huang, Jing; Zhang, Zhiping; Guo, Jian; Ni, Aiguo; Deb, Arjun; Zhang, Lunan; Mirotsou, Maria; Pratt, Richard E; Dzau, Victor J

    2010-01-01

    Rationale Although mesenchymal stem cell (MSC) transplantation has been shown to promote cardiac repair in acute myocardial injury in vivo, its overall restorative capacity appears to be restricted mainly due to poor cell viability and low engraftment in the ischemic myocardium. Specific chemokines are upregulated in the infarcted myocardium. However the expression levels of the corresponding chemokine receptors (e.g. CCR1, CXCR2) in MSCs are very low. We hypothesized that this discordance may account for the poor MSC engraftment and survival. Objective To determine whether overexpression of CCR1 or CXCR2 chemokine receptors in MSCs augments their cell survival, migration and engraftment after injection in the infarcted myocardium. Methods and Results Overexpression of CCR1, but not CXCR2, dramatically increased chemokine-induced murine MSC migration and protected MSC from apoptosis in vitro. Moreover, when MSCs were injected intramyocardially one hour after coronary artery ligation, CCR1-MSCs accumulated in the infarcted myocardium at significantly higher levels than control-MSCs or CXCR2-MSCs three days post-myocardial infarction (MI). CCR1-MSC injected hearts exhibited a significant reduction in infarct size, reduced cardiomyocytes apoptosis and increased capillary density in injured myocardium three days post-MI. Furthermore, intramyocardial injection of CCR1-MSCs prevented cardiac remodeling and restored cardiac function 4 weeks post-MI. Conclusions Our results demonstrate the in vitro and in vivo salutary effects of genetic modification of stem cells. Specifically, overexpression of chemokine receptor enhances the migration, survival and engraftment of MSCs, and may provide a new therapeutic strategy for the injured myocardium. PMID:20378860

  19. Stem cell and epithelial-mesenchymal transition markers are frequently overexpressed in circulating tumor cells of metastatic breast cancer patients

    PubMed Central

    Aktas, Bahriye; Tewes, Mitra; Fehm, Tanja; Hauch, Siegfried; Kimmig, Rainer; Kasimir-Bauer, Sabine

    2009-01-01

    Introduction The persistence of circulating tumor cells (CTC) in breast cancer patients might be associated with stem cell like tumor cells which have been suggested to be the active source of metastatic spread in primary tumors. Furthermore, these cells also may undergo phenotypic changes, known as epithelial-mesenchymal transition (EMT), which allows them to travel to the site of metastasis formation without getting affected by conventional treatment. Here we evaluated 226 blood samples of 39 metastatic breast cancer patients during a follow-up of palliative chemo-, antibody – or hormonal therapy for the expression of the stem cell marker ALDH1 and markers for EMT and correlated these findings with the presence of CTC and response to therapy. Methods 2 × 5 ml blood was analyzed for CTC with the AdnaTest BreastCancer (AdnaGen AG) for the detection of EpCAM, MUC-1 and HER2 transcripts. The recovered c-DNA was additionally multiplex tested for three EMT markers [Twist1, Akt2, PI3Kα] and separately for the tumor stem-cell markers ALDH1. The identification of EMT markers was considered positive if at least one marker was detected in the sample. Results 97% of 30 healthy donor samples investigated were negative for EMT and 95% for ALDH1 transcripts. CTC were detected in 69/226 (31%) cancer samples. In the CTC (+) group, 62% were positive for at least one of the EMT markers and 69% for ALDH1, respectively. In the CTC (-) group the percentages were 7% and 14%, respectively. In non-responders, EMT and ALDH1 expression was found in 62% and 44% of patients, in responders the rates were 10% and 5%, respectively. Conclusions Our data indicate that a major proportion of CTC of metastatic breast cancer patients shows EMT and tumor stem cell characteristics. Further studies are needed to prove whether these markers might serve as an indicator for therapy resistant tumor cell populations and, therefore, an inferior prognosis. PMID:19589136

  20. Generation of Islet-like Cell Aggregates from Human Adipose Tissue-derived Stem Cells by Lentiviral Overexpression of PDX-1

    PubMed Central

    Bahrebar, M.; Soleimani, M.; Karimi, M. H.; Vahdati, A.; Yaghobi, R.

    2015-01-01

    Background: Pancreatic duodenal homeobox1 (PDX-1) is a transcription factor that is important in regulating pancreas development and maintaining β-cell function. β-cell replacement is an effective approach for the treatment of type 1 diabetes. Human adipose-mesenchymal stem cells (hAMSCs) are the ideal population cells for differentiating into insulin-producing cells. Objective: To determine if islet-like cell aggregates production could be generated from hAMSCs by lentiviral overexpression of PDX-1. Methods: After isolation of hAMSCs, characteristics of these cells were identified by flow-cytometic analysis and multilineage differentiation studies. PDX-1 gene delivered into hAMSCs through lentiviral vector for differentiating hAMSCs into insulin-producing cells (IPCs) at the utilized protocol for 14 days. Characteristics of IPCs were evaluated by immunocytofluorescence, dithizone staining, and quantitative reverse transcription PCR. In response to high glucose medium, insulin release was detected by chemiluminescence enzyme immunoassay. Results: The islet-like cell aggregates appeared about 10 days after introduction of PDX-1 into hAMSCs. PDX-1 induced its own expression (auto-induction), a number of islet-related genes such as Ngn3, Nkx2-2, and insulin. The insulin-positive cells were detected in the PDX-1 transduced cells. In response to glucose challenge test, secretion of insulin hormone in the medium with high glucose concentration significantly increased in the PDX-1-transduced cells related to medium with low glucose concentration. Conclusion: Introduction of lentiviral PDX-1 significantly induces hAMSCs to differentiate into islet-like cell aggregates, which may provide a source of adipose stem cells-derived insulin-producing cells for cell replacement therapy in type 1 diabetes. PMID:26082830

  1. Neural Stem Cells Secreting Anti-HER2 Antibody Improve Survival in a Preclinical Model of HER2 Overexpressing Breast Cancer Brain Metastases.

    PubMed

    Kanojia, Deepak; Balyasnikova, Irina V; Morshed, Ramin A; Frank, Richard T; Yu, Dou; Zhang, Lingjiao; Spencer, Drew A; Kim, Julius W; Han, Yu; Yu, Dihua; Ahmed, Atique U; Aboody, Karen S; Lesniak, Maciej S

    2015-10-01

    The treatment of human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer has been revolutionized by trastuzumab. However, longer survival of these patients now predisposes them to forming HER2 positive brain metastases, as the therapeutic antibodies cannot cross the blood brain barrier. The current oncologic repertoire does not offer a rational, nontoxic targeted therapy for brain metastases. In this study, we used an established human neural stem cell line, HB1.F3 NSCs and generated a stable pool of cells secreting a high amount of functional full-length anti-HER2 antibody, equivalent to trastuzumab. Anti-HER2Ab secreted by the NSCs (HER2Ab-NSCs) specifically binds to HER2 overexpressing human breast cancer cells and inhibits PI3K-Akt signaling. This translates to HER2Ab-NSC inhibition of breast cancer cell growth in vitro. Preclinical in vivo experiments using HER2Ab overexpressing NSCs in a breast cancer brain metastases (BCBM) mouse model demonstrate that intracranial injection of HER2Ab-NSCs significantly improves survival. In effect, these NSCs provide tumor localized production of HER2Ab, minimizing any potential off-target side effects. Our results establish HER2Ab-NSCs as a novel, nontoxic, and rational therapeutic approach for the successful treatment of HER2 overexpressing BCBM, which now warrants further preclinical and clinical investigation.

  2. sPLA2 -IIA Overexpression in Mice Epidermis Depletes Hair Follicle Stem Cells and Induces Differentiation Mediated Through Enhanced JNK/c-Jun Activation.

    PubMed

    Sarate, Rahul M; Chovatiya, Gopal L; Ravi, Vagisha; Khade, Bharat; Gupta, Sanjay; Waghmare, Sanjeev K

    2016-09-01

    Secretory phospholipase A2 Group-IIA (sPLA2 -IIA) catalyzes the hydrolysis of the sn-2 position of glycerophospholipids to yield fatty acids and lysophospholipids. sPLA2 -IIA is deregulated in various cancers; however, its role in hair follicle stem cell (HFSC) regulation is obscure. Here we report a transgenic mice overexpressing sPLA2 -IIA (K14-sPLA2 -IIA) showed depletion of HFSC pool. This was accompanied with increased differentiation, loss of ortho-parakeratotic organization and enlargement of sebaceous gland, infundibulum and junctional zone. The colony forming efficiency of keratinocytes was significantly reduced. Microarray profiling of HFSCs revealed enhanced level of epithelial mitogens and transcription factors, c-Jun and FosB that may be involved in proliferation and differentiation. Moreover, K14-sPLA2 -IIA keratinocytes showed enhanced activation of EGFR and JNK1/2 that led to c-Jun activation, which co-related with enhanced differentiation. Further, depletion of stem cells in bulge is associated with high levels of chromatin silencing mark, H3K27me3 and low levels of an activator mark, H3K9ac suggestive of alteration in gene expression contributing toward stem cells differentiation. Our results, first time uncovered that overexpression of sPLA2 -IIA lead to depletion of HFSCs and differentiation associated with altered histone modification. Thus involvement of sPLA2 -IIA in stem cells regulation and disease pathogenesis suggest its prospective clinical implications. Stem Cells 2016;34:2407-2417. PMID:27299855

  3. sPLA2 -IIA Overexpression in Mice Epidermis Depletes Hair Follicle Stem Cells and Induces Differentiation Mediated Through Enhanced JNK/c-Jun Activation.

    PubMed

    Sarate, Rahul M; Chovatiya, Gopal L; Ravi, Vagisha; Khade, Bharat; Gupta, Sanjay; Waghmare, Sanjeev K

    2016-09-01

    Secretory phospholipase A2 Group-IIA (sPLA2 -IIA) catalyzes the hydrolysis of the sn-2 position of glycerophospholipids to yield fatty acids and lysophospholipids. sPLA2 -IIA is deregulated in various cancers; however, its role in hair follicle stem cell (HFSC) regulation is obscure. Here we report a transgenic mice overexpressing sPLA2 -IIA (K14-sPLA2 -IIA) showed depletion of HFSC pool. This was accompanied with increased differentiation, loss of ortho-parakeratotic organization and enlargement of sebaceous gland, infundibulum and junctional zone. The colony forming efficiency of keratinocytes was significantly reduced. Microarray profiling of HFSCs revealed enhanced level of epithelial mitogens and transcription factors, c-Jun and FosB that may be involved in proliferation and differentiation. Moreover, K14-sPLA2 -IIA keratinocytes showed enhanced activation of EGFR and JNK1/2 that led to c-Jun activation, which co-related with enhanced differentiation. Further, depletion of stem cells in bulge is associated with high levels of chromatin silencing mark, H3K27me3 and low levels of an activator mark, H3K9ac suggestive of alteration in gene expression contributing toward stem cells differentiation. Our results, first time uncovered that overexpression of sPLA2 -IIA lead to depletion of HFSCs and differentiation associated with altered histone modification. Thus involvement of sPLA2 -IIA in stem cells regulation and disease pathogenesis suggest its prospective clinical implications. Stem Cells 2016;34:2407-2417.

  4. Nuclear reprogramming of luminal-like breast cancer cells generates Sox2-overexpressing cancer stem-like cellular states harboring transcriptional activation of the mTOR pathway.

    PubMed

    Corominas-Faja, Bruna; Cufí, Sílvia; Oliveras-Ferraros, Cristina; Cuyàs, Elisabet; López-Bonet, Eugeni; Lupu, Ruth; Alarcón, Tomás; Vellon, Luciano; Iglesias, Juan Manuel; Leis, Olatz; Martín, Ángel G; Vazquez-Martin, Alejandro; Menendez, Javier A

    2013-09-15

    Energy metabolism plasticity enables stemness programs during the reprogramming of somatic cells to an induced pluripotent stem cell (iPSC) state. This relationship may introduce a new era in the understanding of Warburg's theory on the metabolic origin of cancer at the level of cancer stem cells (CSCs). Here, we used Yamanaka's stem cell technology in an attempt to create stable CSC research lines in which to dissect the transcriptional control of mTOR--the master switch of cellular catabolism and anabolism--in CSC-like states. The rare colonies with iPSC-like morphology, obtained following the viral transduction of the Oct4, Sox2, Klf4, and c-Myc (OSKM) stemness factors into MCF-7 luminal-like breast cancer cells (MCF-7/Rep), demonstrated an intermediate state between cancer cells and bona fide iPSCs. MCF-7/Rep cells notably overexpressed SOX2 and stage-specific embryonic antigen (SSEA)-4 proteins; however, other stemness-related markers (OCT4, NANOG, SSEA-1, TRA-1-60, and TRA-1-81) were found at low to moderate levels. The transcriptional analyses of OSKM factors confirmed the strong but unique reactivation of the endogenous Sox2 stemness gene accompanied by the silencing of the exogenous Sox2 transgene in MCF-7/Rep cells. Some but not all MCF-7/Rep cells acquired strong alkaline phosphatase (AP) activity compared with MCF-7 parental cells. SOX2-overexpressing MCF-7/Rep cells contained drastically higher percentages of CD44(+) and ALDEFLUOR-stained ALDH(bright) cells than MCF-7 parental cells. The overlap between differentially expressed mTOR signaling-related genes in 3 different SOX2-overexpressing CSC-like cell lines revealed a notable downregulation of 3 genes, PRKAA1 (which codes for the catalytic α 1 subunit of AMPK), DDIT4/REDD1 (a stress response gene that operates as a negative regulator of mTOR), and DEPTOR (a naturally occurring endogenous inhibitor of mTOR activity). The insulin-receptor gene (INSR) was differentially upregulated in MCF-7/Rep cells

  5. Nuclear reprogramming of luminal-like breast cancer cells generates Sox2-overexpressing cancer stem-like cellular states harboring transcriptional activation of the mTOR pathway

    PubMed Central

    Corominas-Faja, Bruna; Cufí, Sílvia; Oliveras-Ferraros, Cristina; Cuyàs, Elisabet; López-Bonet, Eugeni; Lupu, Ruth; Alarcón, Tomás; Vellon, Luciano; Iglesias, Juan Manuel; Leis, Olatz; Martín, Ángel G; Vazquez-Martin, Alejandro; Menendez, Javier A

    2013-01-01

    Energy metabolism plasticity enables stemness programs during the reprogramming of somatic cells to an induced pluripotent stem cell (iPSC) state. This relationship may introduce a new era in the understanding of Warburg’s theory on the metabolic origin of cancer at the level of cancer stem cells (CSCs). Here, we used Yamanaka’s stem cell technology in an attempt to create stable CSC research lines in which to dissect the transcriptional control of mTOR—the master switch of cellular catabolism and anabolism—in CSC-like states. The rare colonies with iPSC-like morphology, obtained following the viral transduction of the Oct4, Sox2, Klf4, and c-Myc (OSKM) stemness factors into MCF-7 luminal-like breast cancer cells (MCF-7/Rep), demonstrated an intermediate state between cancer cells and bona fide iPSCs. MCF-7/Rep cells notably overexpressed SOX2 and stage-specific embryonic antigen (SSEA)-4 proteins; however, other stemness-related markers (OCT4, NANOG, SSEA-1, TRA-1–60, and TRA-1–81) were found at low to moderate levels. The transcriptional analyses of OSKM factors confirmed the strong but unique reactivation of the endogenous Sox2 stemness gene accompanied by the silencing of the exogenous Sox2 transgene in MCF-7/Rep cells. Some but not all MCF-7/Rep cells acquired strong alkaline phosphatase (AP) activity compared with MCF-7 parental cells. SOX2-overexpressing MCF-7/Rep cells contained drastically higher percentages of CD44+ and ALDEFLUOR-stained ALDHbright cells than MCF-7 parental cells. The overlap between differentially expressed mTOR signaling-related genes in 3 different SOX2-overexpressing CSC-like cell lines revealed a notable downregulation of 3 genes, PRKAA1 (which codes for the catalytic α 1 subunit of AMPK), DDIT4/REDD1 (a stress response gene that operates as a negative regulator of mTOR), and DEPTOR (a naturally occurring endogenous inhibitor of mTOR activity). The insulin-receptor gene (INSR) was differentially upregulated in MCF-7/Rep

  6. MiR-1207 overexpression promotes cancer stem cell-like traits in ovarian cancer by activating the Wnt/β-catenin signaling pathway.

    PubMed

    Wu, Geyan; Liu, Aibin; Zhu, Jinrong; Lei, Fangyong; Wu, Shu; Zhang, Xin; Ye, Liping; Cao, Lixue; He, Shanyang

    2015-10-01

    Wnt/β-catenin signaling pathway is strictly controlled by multiple negative regulators. However, how tumor cells override the negative regulatory effects to maintain constitutive activation of Wnt/β-catenin signaling, which is commonly observed in various cancers, remains puzzling. In current study, we reported that overexpression of miR-1207 in ovarian cancer activated Wnt/β-catenin signaling by directly targeting and suppressing secreted Frizzled-related protein 1 (SFRP1), AXIN2 and inhibitor of β-catenin and TCF-4 (ICAT), which are vital negative regulators of the Wnt/β-catenin pathway. We found that the expression of miR-1207 was ubiquitously upregulated in both ovarian cancer tissues and cells, which inversely correlated with patient overall survival. Furthermore, overexpression of miR-1207 enhanced, while silencing miR-1207 reduced, stem cell-like traits of ovarian cancer cells in vitro and in vivo, including tumor sphere formation capability and proportion of SP+ and CD133+ cells. Importantly, upregulating miR-1207 promoted, while silencing miR-1207 inhibited, the tumorigenicity of ovarian cancer cells. Hence, our results suggest that miR-1207 plays a vital role in promoting the cancer stem cell-like phenotype in ovarian cancer and might represent a potential target for anti-ovarian cancer therapy.

  7. Overexpression of the MRI Reporter Genes Ferritin and Transferrin Receptor Affect Iron Homeostasis and Produce Limited Contrast in Mesenchymal Stem Cells

    PubMed Central

    Pereira, Sofia M.; Moss, Diana; Williams, Steve R.; Murray, Patricia; Taylor, Arthur

    2015-01-01

    Imaging technologies that allow the non-invasive monitoring of stem cells in vivo play a vital role in cell-based regenerative therapies. Recently, much interest has been generated in reporter genes that enable simultaneous monitoring of the anatomical location and viability of cells using magnetic resonance imaging (MRI). Here, we investigate the efficacy of ferritin heavy chain-1 (Fth1) and transferrin receptor-1 (TfR1) as reporters for tracking mesenchymal stem cells. The overexpression of TfR1 was well tolerated by the cells but Fth1 was found to affect the cell’s iron homeostasis, leading to phenotypic changes in the absence of iron supplementation and an upregulation in transcript and protein levels of the cell’s endogenous transferrin receptor. Neither the sole overexpression of Fth1 nor TfR1 resulted in significant increases in intracellular iron content, although significant differences were seen when the two reporter genes were used in combination, in the presence of high concentrations of iron. The supplementation of the culture medium with iron sources was a more efficient means to obtain contrast than the use of reporter genes, where high levels of intracellular iron were reflected in transverse (T2) relaxation. The feasibility of imaging iron-supplemented cells by MRI is shown using a 3R-compliant chick embryo model. PMID:26184159

  8. Overexpression of molecular chaperons GRP78 and GRP94 in CD44hi/CD24lo breast cancer stem cells

    PubMed Central

    Nami, Babak; Ghasemi-Dizgah, Armin; Vaseghi, Akbar

    2016-01-01

    Introduction: Breast cancer stem cell with CD44hi/CD24lo phonotype is described having stem cell properties and represented as the main driving factor in breast cancer initiation, growth, metastasis and low response to anti-cancer agents. Glucoseregulated proteins (GRPs) are heat shock protein family chaperons that are charged with regulation of protein machinery and modulation of endoplasmic reticulum homeostasis whose important roles in stem cell development and invasion of various cancers have been demonstrated. Here, we investigated the expression levels of GRP78 and GRP94 in CD44hi/CD24lo phenotype breast cancer stem cells (BCSCs). Methods: MCF7, T-47D and MDA-MB-231 breast cancer cell lines were used. CD44hi/CD24lo phenotype cell population were analyzed and sorted by fluorescence-activated cell sorting (FACS). Transcriptional and translational expression of GRP78 and GRP94 were investigated by western blotting and quantitative real time PCR. Results: Results showed different proportion of CD44hi/CD24lo phenotype cell population in their original bulk cells. The ranking of the cell lines in terms of CD44hi/CD24lo phenotype cell population was as MCF7cells exhibited higher mRNA and protein expression level of GRP78 and GRP94 compared to their original bulk cells. Conclusion: Our results show a relationship between overexpression of GRP78 and GRP94 and exhibiting CD44hi/CD24lo phenotype in breast cancer cells. We conclude that upregulation of GRPs may be an important factor in the emergence of CD44hi/CD24lo phenotype BCSCs features. PMID:27525228

  9. 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

  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

    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 LMVs(miRCtrl) and LMVs(miR34a). The effect of miR34a transfection on LSC proliferation and the effects of LMVs(miRCtrl) or LMVs(miR34a) 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) LMVs(miRCtrl) 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 LMVs(miR34a); (3) LMVs(miR34a) produced opposite effects as compared with LMVs(miRCtrl), 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. Perturbation of Auxin Homeostasis by Overexpression of Wild-Type IAA15 Results in Impaired Stem Cell Differentiation and Gravitropism in Roots

    PubMed Central

    Yan, Da-Wei; Wang, Jing; Yuan, Ting-Ting; Hong, Li-Wei; Gao, Xiang; Lu, Ying-Tang

    2013-01-01

    Aux/IAAs interact with auxin response factors (ARFs) to repress their transcriptional activity in the auxin signaling pathway. Previous studies have focused on gain-of-function mutations of domain II and little is known about whether the expression level of wild-type Aux/IAAs can modulate auxin homeostasis. Here we examined the perturbation of auxin homeostasis by ectopic expression of wild-type IAA15. Root gravitropism and stem cell differentiation were also analyzed. The transgenic lines were less sensitive to exogenous auxin and exhibited low-auxin phenotypes including failures in gravity response and defects in stem cell differentiation. Overexpression lines also showed an increase in auxin concentration and reduced polar auxin transport. These results demonstrate that an alteration in the expression of wild-type IAA15 can disrupt auxin homeostasis. PMID:23472140

  12. Myocardin-related transcription factor-A-overexpressing bone marrow stem cells protect cardiomyocytes and alleviate cardiac damage in a rat model of acute myocardial infarction.

    PubMed

    Zhong, Ze; Hu, Jia-Qing; Wu, Xin-Dong; Sun, Yong; Jiang, Jun

    2015-09-01

    Myocardin-related transcription factor-A (MRTF-A) can transduce biomechanical and humoral signals, which can positively modulate cardiac damage induced by acute myocardial infarction (AMI). In the clinic, bone marrow stem cell (BMSC) therapy is being increasingly utilized for AMI; however, the effects of BMSC transplantation remain to be optimized. Therefore, a novel strategy to enhance BMSC‑directed myocardial repair is particularly important. The present study was performed to assess the efficacy of MRTF‑A-overexpressing BMSCs in a rat model of AMI. Primary cardiomyocytes were prepared from neonatal Sprague-Dawley rats and BMSCs were isolated from male Sprague-Dawley rats (aged 8-12 weeks). Annexin V-phycoerythrin/7-actinomycin D staining was used to evaluate BMSC and cardiomyocyte survival after exposure to hydrogen peroxide in vitro. B-cell lymphoma 2 (Bcl-2) protein expression was measured by flow cytometric and western blot analyses. The effects of MRTF-A‑overexpressing BMSCs in a rat model of AMI were investigated by hematoxylin and eosin staining and western blot analysis of Bcl-2 expression in myocardial tissue sections. MRTF-A enhanced the migration of BMSCs, and overexpression of MRTF-A in BMSCs prevented hydrogen peroxide-induced apoptosis in primary cardiomyocytes ex vivo. In addition, co-culture of cardiomyocytes with MRTF‑A-overexpressing BMSCs inhibited hydrogen peroxide-induced apoptosis and the enhanced expression of Bcl-2. Furthermore, in vivo, enhanced cell survival was observed in the MRTF-A-modified BMSC group compared with that in the control group. These observations indicated that MRTF-A-overexpressing BMSCs have the potential to exert cardioprotective effects against hydrogen peroxide-induced injury and that treatment with MRTF‑A‑modified BMSCs is able to reverse cardiac dysfunction after AMI.

  13. Overexpression of mitochondrial Hsp75 protects neural stem cells against microglia-derived soluble factor-induced neurotoxicity by regulating mitochondrial permeability transition pore opening in vitro

    PubMed Central

    WANG, YAN; LIN, JIZONG; CHEN, QING-ZHUANG; ZHU, NING; JIANG, DE-QI; LI, MING-XING; WANG, YONG

    2015-01-01

    Microglia (MG)-induced neurotoxicity, a major determinant of Alzheimer's disease, is closely related to the survival of neural stem cells (NSCs). Heat shock protein 75 (Hsp75) has been reported to exert protective effects against environmental stresses; however, whether or not it protects NSCs against MG-derived soluble factor-induced neurotoxicity remains unclear. In the present study, we constructed NSCs that overexpressed human Hsp75 protein and established a co-culture system in order to elucidate the role of Hsp75 in NSC-MG interactions. The results obtained indicated that Hsp75 expression increased after 12 h of soluble factor induction and continued to increase for up to 36 h of treatment. The overexpression of Hsp75 decreased NSC apoptosis and preserved mitochondrial membrane potential. Further experiments revealed that the overexpression of Hsp75 inhibited the formation of cyclophilin D (CypD)-dependent mitochondrial permeability transition pore (mPTP) involvement in neurotoxicity-mediated mitochondrial dysfunction and suppressed the activation of the mitochondrial apoptotic cascade, as demonstrated by the inhibition of the release of cytochrome c (Cytc) and the activation of caspase-3. The findings of this study demonstrate that Hsp75 overexpression prevents the impairment of NSCs induced by MG-derived soluble factors by regulating the opening of mPTP. Thus, Hsp75 warrants further investigation as a potential candidate for protection against neurotoxicity. PMID:26500047

  14. 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 ...

  15. Co-transplantation of GDNF-overexpressing neural stem cells and fetal dopaminergic neurons mitigates motor symptoms in a rat model of Parkinson's disease.

    PubMed

    Deng, Xingli; Liang, Yuanxin; Lu, Hua; Yang, Zhiyong; Liu, Ru'en; Wang, Jinkun; Song, Xiaobin; Long, Jiang; Li, Yu; Lei, Deqiang; Feng, Zhongtang

    2013-01-01

    Striatal transplantation of dopaminergic (DA) neurons or neural stem cells (NSCs) has been reported to improve the symptoms of Parkinson's disease (PD), but the low rate of cell survival, differentiation, and integration in the host brain limits the therapeutic efficacy. We investigated the therapeutic effects of intracranial co-transplantation of mesencephalic NSCs stably overexpressing human glial-derived neurotrophic factor (GDNF-mNSCs) together with fetal DA neurons in the 6-OHDA rat model of PD. Striatal injection of mNSCs labeled by the contrast enhancer superparamagnetic iron oxide (SPIO) resulted in a hypointense signal in the striatum on T2-weighted magnetic resonance images that lasted for at least 8 weeks post-injection, confirming the long-term survival of injected stem cells in vivo. Co-transplantation of GDNF-mNSCs with fetal DA neurons significantly reduced apomorphine-induced rotation, a behavioral endophenotype of PD, compared to sham-treated controls, rats injected with mNSCs expressing empty vector (control mNSCs) plus fetal DA neurons, or rats injected separately with either control mNSCs, GDNF-mNSCs, or fetal DA neurons. In addition, survival and differentiation of mNSCs into DA neurons was significantly greater following co-transplantation of GDNF-mNSCs plus fetal DA neurons compared to the other treatment groups as indicated by the greater number of cell expressing both the mNSCs lineage tracer enhanced green fluorescent protein (eGFP) and the DA neuron marker tyrosine hydroxylase. The success of cell-based therapies for PD may be greatly improved by co-transplantation of fetal DA neurons with mNSCs genetically modified to overexpress trophic factors such as GDNF that support differentiation into DA cells and their survival in vivo.

  16. Human neural stem cells survive long term in the midbrain of dopamine-depleted monkeys after GDNF overexpression and project neurites toward an appropriate target.

    PubMed

    Wakeman, Dustin R; Redmond, D Eugene; Dodiya, Hemraj B; Sladek, John R; Leranth, Csaba; Teng, Yang D; Samulski, R Jude; Snyder, Evan Y

    2014-06-01

    Transplanted multipotent human fetal neural stem cells (hfNSCs) significantly improved the function of parkinsonian monkeys in a prior study primarily by neuroprotection, with only 3%-5% of cells expressing a dopamine (DA) phenotype. In this paper, we sought to determine whether further manipulation of the neural microenvironment by overexpression of a developmentally critical molecule, glial cell-derived neurotrophic factor (GDNF), in the host striatum could enhance DA differentiation of hfNSCs injected into the substantia nigra and elicit growth of their axons to the GDNF-expressing target. hfNSCs were transplanted into the midbrain of 10 green monkeys exposed to 1-methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine. GDNF was delivered concomitantly to the striatum via an adeno-associated virus serotype 5 vector, and the fate of grafted cells was assessed after 11 months. Donor cells remained predominantly within the midbrain at the injection site and sprouted numerous neurofilament-immunoreactive fibers that appeared to course rostrally toward the striatum in parallel with tyrosine hydroxylase-immunoreactive fibers from the host substantia nigra but did not mature into DA neurons. This work suggests that hfNSCs can generate neurons that project long fibers in the adult primate brain. However, in the absence of region-specific signals and despite GDNF overexpression, hfNSCs did not differentiate into mature DA neurons in large numbers. It is encouraging, however, that the adult primate brain appeared to retain axonal guidance cues. We believe that transplantation of stem cells, specifically instructed ex vivo to yield DA neurons, could lead to reconstruction of some portion of the nigrostriatal pathway and prove beneficial for the parkinsonian condition.

  17. The transplantation of Akt-overexpressing amniotic fluid-derived mesenchymal stem cells protects the heart against ischemia-reperfusion injury in rabbits

    PubMed Central

    WANG, YAN; LI, YIGANG; SONG, LEI; LI, YANYAN; JIANG, SHAN; ZHANG, SONG

    2016-01-01

    Amniotic fluid-derived mesenchymal stem cells (AFMSCs) are an attractive cell source for applications in regenerative medicine, due to characteristics such as proliferative capacity and multipotency. In addition, Akt, a serine-threonine kinase, maintains stem cells by promoting viability and proliferation. Whether the transplantation of Akt-overexpressing AFMSCs protects the heart against ischemia-reperfusion (I/R) injury has yet to be elucidated. Accordingly, the Akt gene was overexpressed in AFMSCs using lentiviral transduction, and Akt-AFMSCs were transplanted into the ischemic myocardium of rabbits prior to reperfusion. Any protective effects resulting from this procedure were subsequently sought after three weeks later. A histological examination revealed that there was a decrease in intramyocardial inflammation and ultrastructural damage, and an increase in capillary density and in the levels of GATA binding protein 4, connexin 43 and cardiac troponin T in the Akt-AFMSC group compared with the control group. A significant decrease in cardiomyocyte apoptosis, accompanying an increase in phosphorylated Akt and B-cell lymphoma 2 (Bcl-2) and a decrease in caspase-3, was also observed. Furthermore, the left ventricular function was markedly augmented in the Akt-AFMSC group compared with the control group. These observations suggested that the protective effect of AFMSCs may be due to the delivery of secreted cytokines, promotion of neoangiogenesis, prevention of cardiomyocyte apoptosis, transdifferentiation into cardiomyocytes and promotion of the viability of AFMSCs, which are assisted by Akt gene modification. Taken together, the results of the present study have indicated that transplantation of Akt-AFMSCs is able to alleviate myocardial I/R injury and improve cardiac function. PMID:27151366

  18. Human Mesenchymal Stem Cells Genetically Engineered to Overexpress Brain-derived Neurotrophic Factor Improve Outcomes in Huntington's Disease Mouse Models

    PubMed Central

    Pollock, Kari; Dahlenburg, Heather; Nelson, Haley; Fink, Kyle D; Cary, Whitney; Hendrix, Kyle; Annett, Geralyn; Torrest, Audrey; Deng, Peter; Gutierrez, Joshua; Nacey, Catherine; Pepper, Karen; Kalomoiris, Stefanos; D Anderson, Johnathon; McGee, Jeannine; Gruenloh, William; Fury, Brian; Bauer, Gerhard; Duffy, Alexandria; Tempkin, Theresa; Wheelock, Vicki; Nolta, Jan A

    2016-01-01

    Huntington's disease (HD) is a fatal degenerative autosomal dominant neuropsychiatric disease that causes neuronal death and is characterized by progressive striatal and then widespread brain atrophy. Brain-derived neurotrophic factor (BDNF) is a lead candidate for the treatment of HD, as it has been shown to prevent cell death and to stimulate the growth and migration of new neurons in the brain in transgenic mouse models. BDNF levels are reduced in HD postmortem human brain. Previous studies have shown efficacy of mesenchymal stem/stromal cells (MSC)/BDNF using murine MSCs, and the present study used human MSCs to advance the therapeutic potential of the MSC/BDNF platform for clinical application. Double-blinded studies were performed to examine the effects of intrastriatally transplanted human MSC/BDNF on disease progression in two strains of immune-suppressed HD transgenic mice: YAC128 and R6/2. MSC/BDNF treatment decreased striatal atrophy in YAC128 mice. MSC/BDNF treatment also significantly reduced anxiety as measured in the open-field assay. Both MSC and MSC/BDNF treatments induced a significant increase in neurogenesis-like activity in R6/2 mice. MSC/BDNF treatment also increased the mean lifespan of the R6/2 mice. Our genetically modified MSC/BDNF cells set a precedent for stem cell-based neurotherapeutics and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis, Alzheimer's disease, and some forms of Parkinson's disease. These cells provide a platform delivery system for future studies involving corrective gene-editing strategies. PMID:26765769

  19. Human Mesenchymal Stem Cells Genetically Engineered to Overexpress Brain-derived Neurotrophic Factor Improve Outcomes in Huntington's Disease Mouse Models.

    PubMed

    Pollock, Kari; Dahlenburg, Heather; Nelson, Haley; Fink, Kyle D; Cary, Whitney; Hendrix, Kyle; Annett, Geralyn; Torrest, Audrey; Deng, Peter; Gutierrez, Joshua; Nacey, Catherine; Pepper, Karen; Kalomoiris, Stefanos; D Anderson, Johnathon; McGee, Jeannine; Gruenloh, William; Fury, Brian; Bauer, Gerhard; Duffy, Alexandria; Tempkin, Theresa; Wheelock, Vicki; Nolta, Jan A

    2016-05-01

    Huntington's disease (HD) is a fatal degenerative autosomal dominant neuropsychiatric disease that causes neuronal death and is characterized by progressive striatal and then widespread brain atrophy. Brain-derived neurotrophic factor (BDNF) is a lead candidate for the treatment of HD, as it has been shown to prevent cell death and to stimulate the growth and migration of new neurons in the brain in transgenic mouse models. BDNF levels are reduced in HD postmortem human brain. Previous studies have shown efficacy of mesenchymal stem/stromal cells (MSC)/BDNF using murine MSCs, and the present study used human MSCs to advance the therapeutic potential of the MSC/BDNF platform for clinical application. Double-blinded studies were performed to examine the effects of intrastriatally transplanted human MSC/BDNF on disease progression in two strains of immune-suppressed HD transgenic mice: YAC128 and R6/2. MSC/BDNF treatment decreased striatal atrophy in YAC128 mice. MSC/BDNF treatment also significantly reduced anxiety as measured in the open-field assay. Both MSC and MSC/BDNF treatments induced a significant increase in neurogenesis-like activity in R6/2 mice. MSC/BDNF treatment also increased the mean lifespan of the R6/2 mice. Our genetically modified MSC/BDNF cells set a precedent for stem cell-based neurotherapeutics and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis, Alzheimer's disease, and some forms of Parkinson's disease. These cells provide a platform delivery system for future studies involving corrective gene-editing strategies. PMID:26765769

  20. Intracoronary Transplantation of Mesenchymal Stem Cells with Overexpressed Integrin-Linked Kinase Improves Cardiac Function in Porcine Myocardial Infarction

    PubMed Central

    Mu, Dan; Zhang, Xin-Lin; Xie, Jun; Yuan, Hui-Hua; Wang, Kun; Huang, Wei; Li, Guan-Nan; Lu, Jian-Rong; Mao, Li-Juan; Wang, Lian; Cheng, Le; Mai, Xiao-Li; Yang, Jun; Tian, Chuan-Shuai; Kang, Li-Na; Gu, Rong; Zhu, Bin; Xu, Biao

    2016-01-01

    The effect of mesenchymal stem cell (MSCs)-based therapy on treating acute myocardial infarction (MI) is limited due to poor engraftment and limited regenerative potential. Here we engineered MSCs with integrin-linked kinase (ILK), a pleiotropic protein critically regulating cell survival, proliferation, differentiation, and angiogenesis. We firstly combined ferumoxytol with poly-L-lysine (PLL), and found this combination promisingly enabled MRI visualization of MSCs in vitro and in vivo with good safety. We provided visually direct evidence that intracoronary ILK-MSCs had substantially enhanced homing capacity to infarct myocardium in porcine following cardiac catheterization induced MI. Intracoronary transplantation of allogeneic ILK-MSCs, but not vector-MSCs, significantly enhanced global left ventricular ejection fraction (LVEF) by 7.8% compared with baseline, by 10.3% compared with vehicles, and inhibited myocardial remodeling compared with vehicles at 15-day follow-up. Compared with vector-MSCs, ILK-MSCs significantly improved regional LV contractile function, reduced scar size, fibrosis, cell apoptosis, and increased regional myocardial perfusion and cell proliferation. This preclinical study indicates that ILK-engineered MSCs might promote the clinical translation of MSC-based therapy in post-MI patients, and provides evidence that ferumoxytol labeling of cells combined with PLL is feasible in in vivo cell tracking. PMID:26750752

  1. Overexpression of Glutamate Decarboxylase in Mesenchymal Stem Cells Enhances Their Immunosuppressive Properties and Increases GABA and Nitric Oxide Levels

    PubMed Central

    González, Marisol; Vilches, Rodrigo; Rojas, Pablo; Vásquez, Manuel; Kurte, Mónica; Vega-Letter, Ana María; Carrión, Flavio; Figueroa, Fernando; Rojas, Patricio; Irarrázabal, Carlos

    2016-01-01

    The neurotransmitter GABA has been recently identified as a potent immunosuppressive agent that targets both innate and adaptive immune systems and prevents disease progression of several autoimmunity models. Mesenchymal stem cells (MSCs) are self-renewing progenitor cells that differentiate into various cell types under specific conditions, including neurons. In addition, MSC possess strong immunosuppressive capabilities. Upon cytokine priming, undifferentiated MSC suppress T-cell proliferation via cell-to-cell contact mechanisms and the secretion of soluble factors like nitric oxide, prostaglandin E2 and IDO. Although MSC and MSC-derived neuron-like cells express some GABAergic markers in vitro, the role for GABAergic signaling in MSC-mediated immunosuppression remains completely unexplored. Here, we demonstrate that pro-inflammatory cytokines selectively regulate GAD-67 expression in murine bone marrow-MSC. However, expression of GAD-65 is required for maximal GABA release by MSC. Gain of function experiments using GAD-67 and GAD-65 co-expression demonstrates that GAD increases immunosuppressive function in the absence of pro-inflammatory licensing. Moreover, GAD expression in MSC evokes an increase in both GABA and NO levels in the supernatants of co-cultured MSC with activated splenocytes. Notably, the increase in NO levels by GAD expression was not observed in cultures of isolated MSC expressing GAD, suggesting crosstalk between these two pathways in the setting of immunosuppression. These results indicate that GAD expression increases MSC-mediated immunosuppression via secretion of immunosuppressive agents. Our findings may help reconsider GABAergic activation in MSC for immunological disorders. PMID:27662193

  2. Magnetofection Mediated Transient NANOG Overexpression Enhances Proliferation and Myogenic Differentiation of Human Hair Follicle Derived Mesenchymal Stem Cells.

    PubMed

    Son, Seoyoung; Liang, Mao-Shih; Lei, Pedro; Xue, Xiaozheng; Furlani, Edward P; Andreadis, Stelios T

    2015-07-15

    We used magnetofection (MF) to achieve high transfection efficiency into human mesenchymal stem cells (MSCs). A custom-made magnet array, matching well-to-well to a 24-well plate, was generated and characterized. Theoretical predictions of magnetic force distribution within each well demonstrated that there was no magnetic field interference among magnets in adjacent wells. An optimized protocol for efficient gene delivery to human hair follicle derived MSCs (hHF-MSCs) was established using an egfp-encoding plasmid, reaching approximately ∼50% transfection efficiency without significant cytotoxicity. Then we applied the optimized MF protocol to express the pluripotency-associated transcription factor NANOG, which was previously shown to reverse the effects of organismal aging on MSC proliferation and myogenic differentiation capacity. Indeed, MF-mediated NANOG delivery increased proliferation and enhanced the differentiation of hHF-MSCs into smooth muscle cells (SMCs). Collectively, our results show that MF can achieve high levels of gene delivery to MSCs and, therefore, may be employed to moderate or reverse the effects of cellular senescence or reprogram cells to the pluripotent state without permanent genetic modification.

  3. Human Stem Cells Overexpressing miR-21 Promote Angiogenesis in Critical Limb Ischemia by Targeting CHIP to Enhance HIF-1α Activity.

    PubMed

    Zhou, Yong; Zhu, Youming; Zhang, Li; Wu, Tao; Wu, Tingting; Zhang, Wenjie; Decker, Ann Marie; He, Jiacai; Liu, Jie; Wu, Yiqun; Jiang, Xinqun; Zhang, Zhiyuan; Liang, Chaozhao; Zou, Duohong

    2016-04-01

    Critical limb ischemia (CLI) is a severe blockage in the arteries of the lower extremities. However, the effective and optimal treatment for CLI remains to be elucidated. Previous therapeutic research is mainly focused on proangiogenic growth factors administrations. Recently, miR-21 has been revealed to play a crucial role in angiogenesis. Thus, we hypothesize that miR-21 over-expression in human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) can effectively treat CLI. Herein, UCBMSCs were transduced with lentivirus-miR-21-Luciferase (Lenti-miR-21) or lentivirus- LacZ-Luciferase (Lenti-LacZ). The results indicated that miR-21 induced UCBMSCs proliferation, migration, and angiogenesis in vitro. Subsequently, general observation and laser Doppler perfusion imaging were introduced to detect perfusion in muscles of CLI-nude mice on 1, 4, 7, 14, and 28 day postoperation. There was a significant improvement in blood vessels of the ischemic limb in Lenti-miR-21 group at 7 day compared with the saline or Lenti-LacZ groups. At 28 day, histological analysis confirmed that UCBMSCs over-expressing miR-21 increased neovascularization in CLI. Furthermore, carboxyl terminus of Hsc70-interacting protein (CHIP) was found to be the target gene for miR-21-mediated activation of hypoxia-inducible factor 1α (HIF-1α) in UCBMSCs. In summary, our study demonstrated that over-expressing miR-21 in UCBMSCs could improve neovascularization in CLI through enhancing HIF-1α activity by targeting CHIP, which may hold great therapeutic promise in treating CLI.

  4. Dual targeting and enhanced cytotoxicity to HER2-overexpressing tumors by immunoapoptotin-armored mesenchymal stem cells.

    PubMed

    Cai, Yanhui; Xi, Yujing; Cao, Zhongyuan; Xiang, Geng; Ni, Qingrong; Zhang, Rui; Chang, Jing; Du, Xiao; Yang, Angang; Yan, Bo; Zhao, Jing

    2016-10-10

    Mesenchymal stem cells (MSCs) are promising vehicles for the delivery of anticancer agents in cancer therapy. However, the tumor targeting of loaded therapeutics is essential. Here, we explored a dual-targeting strategy to incorporate tumor-tropic MSC delivery with HER2-specific killing by the immunoapoptotin e23sFv-Fdt-tBid generated in our previous studies. The MSC engineering allowed simultaneous immunoapoptotin secretion and bioluminescence detection of the modified MSCs. Systemic administration of the immunoapoptotin-engineered MSCs was investigated in human HER2-reconstituted syngeneic mouse models of orthotopic and metastatic breast cancer, as well as in a xenograft nude mouse model of orthotopic gastric cancer. In vivo dual tumor targeting was confirmed by local accumulation of the bioluminescence-imaged MSCs and persistence of His-immunostained immunoapoptotins in tumor sites. The added tumor preference of MSC-secreted immunoapoptotins resulted in a significantly stronger antitumor effect compared with purified immunoapoptotins and Jurkat-delivered immunoapoptotins. This immunoapoptotin-armored MSC strategy provides a rationale for its use in extended malignancies by combining MSC mobility with redirected immunoapoptotins against a given tumor antigen. PMID:27473824

  5. Over-expression of HO-1 on mesenchymal stem cells promotes angiogenesis and improves myocardial function in infarcted myocardium

    PubMed Central

    2010-01-01

    Heme oxygenase-1 (HO-1) is a stress-inducible enzyme with diverse cytoprotective effects, and reported to have an important role in angiogenesis recently. Here we investigated whether HO-1 transduced by mesenchymal stem cells (MSCs) can induce angiogenic effects in infarcted myocardium. HO-1 was transfected into cultured MSCs using an adenoviral vector. 1 × 106 Ad-HO-1-transfected MSCs (HO-1-MSCs) or Ad-Null-transfected MSCs (Null-MSCs) or PBS was respectively injected into rat hearts intramyocardially at 1 h post-myocardial infarction. The results showed that HO-1-MSCs were able to induce stable expression of HO-1 in vitro and in vivo. The capillary density and expression of angiogenic growth factors, VEGF and FGF2 were significantly enhanced in HO-1-MSCs-treated hearts compared with Null-MSCs-treated and PBS-treated hearts. However, the angiogenic effects of HO-1 were abolished by treating the animals with HO inhibitor, zinc protoporphyrin. The myocardial apoptosis was marked reduced with significantly reduced fibrotic area in HO-1-MSCs-treated hearts; Furthermore, the cardiac function and remodeling were also significantly improved in HO-1-MSCs-treated hearts. Our current findings support the premise that HO-1 transduced by MSCs can induce angiogenic effects and improve heart function after acute myocardial infarction. PMID:20925964

  6. Netrin-1 overexpression in bone marrow mesenchymal stem cells promotes functional recovery in a rat model of peripheral nerve injury

    PubMed Central

    Ke, Xianjin; Li, Qian; Xu, Li; Zhang, Ying; Li, Dongmei; Ma, Jianhua; Mao, Xiaoming

    2015-01-01

    Abstract Transplantation of bone marrow mesenchymal stem cells (BMSCs) has been developed as a new method of treating diseases of the peripheral nervous system. While netrin-1 is a critical molecule for axonal path finding and nerve growth, it may also affect vascular network formation. Here, we investigated the effect of transplanting BMSCs that produce netrin-1 in a rat model of sciatic nerve crush injury. We introduced a sciatic nerve crush injury, and then injected 1×106 BMSCs infected by a recombinant adenovirus expressing netrin-1 Ad5-Netrin-1-EGFP or culture medium into the injured part in the next day. At day 7, 14 and 28 after injection, we measured motor nerve conduction and detected mRNA expressions of netrin-1 receptors UNC5B and Deleted in Colorectal Cancer (DCC), and neurotrophic factors brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) by real-time PCR. We also detected protein expressions of BDNF and NGF by Western blotting assays and examined BMSCs that incorporated into myelin and vascellum. The results showed that BMSCs infected by Ad5-Netrin-1-EGFP significantly improved the function of the sciatic nerve, and led to increased expression of BDNF and NGF (P<0.05). Moreover, 28 days after injury, more Schwann cells were found in BMSCs infected by Ad5-Netrin-1-EGFP compared to control BMSCs. In conclusion, transplantation of BMSCs that produce netrin-1 improved the function of the sciatic nerve after injury. This method may be a new treatment of nerve injury. PMID:26445571

  7. Cell Therapy Using Bone Marrow-Derived Stem Cell Overexpressing BMP-7 for Degenerative Discs in a Rat Tail Disc Model.

    PubMed

    Liao, Jen-Chung

    2016-01-01

    Degenerative discs can cause low back pain. Cell-based transplantation or growth factors therapy have been suggested as a strategy to stimulate disc regeneration. Bone marrow-derived mesenchymal stem cells (BMDMSC) containing bone morphogenetic protein-7 (BMP-7) gene were constructed. We evaluated the effectiveness of these BMP-7 overexpressing cells on degenerative discs in rat tails. In vitro and in vivo studies were designed. In the first stage, the rats were divided into two group according to discs punctured by different needle gauges (18 gauge and 22 gauge). In the second stage, the ideal size of needle was used to induce rat tail disc degeneration. These animals are divided into three groups according to timing of treatment (zero-week, two-week, four-week). Each group was divided into three treating subgroups: control group, BMDMSC group, and Baculo-BMP-7-BMDMSC group. Each rat undergoes radiography examination every two weeks. After eight weeks, the discs were histologically examined with hematoxylin and eosin stain and Alcian blue stain. The 18-gauge group exhibited significant decrease in disc height index (%) than 22-gauge group at eight weeks at both Co6-7 (58.1% ± 2.8% vs. 63.7% ± 1.0%, p = 0.020) and Co8-9 discs (62.7% ± 2.8% vs. 62.8% ± 1.5%, p = 0.010). Baculo-BMP-7-BMDMSCs group showed significant difference in disc height index compared to the BMDMSCs group at both Co6-7 (93.7% ± 1.5% vs. 84.8% ± 1.0%, p = 0.011) and Co8-9 (86.0% ± 2.1% vs. 81.8% ± 1.7%, p = 0.012). In Baculo-BMP-7-BMDMSCs group, the zero-week treatment subgroup showed significant better in disc height index compared to two-week treatment group (p = 0.044), and four-week treatment group (p = 0.011). The zero-week treatment subgroup in Baculo-BMP-7-BMDMSCs group also had significant lower histology score than two-week treatment (4.3 vs. 5.7, p = 0.045) and four-week treatment (4.3 vs. 6.0, p = 0.031). In conclusion, Baculo-BMP-7-BMDMSC can slow down the progression of disc

  8. Cell Therapy Using Bone Marrow-Derived Stem Cell Overexpressing BMP-7 for Degenerative Discs in a Rat Tail Disc Model

    PubMed Central

    Liao, Jen-Chung

    2016-01-01

    Degenerative discs can cause low back pain. Cell-based transplantation or growth factors therapy have been suggested as a strategy to stimulate disc regeneration. Bone marrow-derived mesenchymal stem cells (BMDMSC) containing bone morphogenetic protein-7 (BMP-7) gene were constructed. We evaluated the effectiveness of these BMP-7 overexpressing cells on degenerative discs in rat tails. In vitro and in vivo studies were designed. In the first stage, the rats were divided into two group according to discs punctured by different needle gauges (18 gauge and 22 gauge). In the second stage, the ideal size of needle was used to induce rat tail disc degeneration. These animals are divided into three groups according to timing of treatment (zero-week, two-week, four-week). Each group was divided into three treating subgroups: control group, BMDMSC group, and Baculo-BMP-7-BMDMSC group. Each rat undergoes radiography examination every two weeks. After eight weeks, the discs were histologically examined with hematoxylin and eosin stain and Alcian blue stain. The 18-gauge group exhibited significant decrease in disc height index (%) than 22-gauge group at eight weeks at both Co6-7 (58.1% ± 2.8% vs. 63.7% ± 1.0%, p = 0.020) and Co8-9 discs (62.7% ± 2.8% vs. 62.8% ± 1.5%, p = 0.010). Baculo-BMP-7-BMDMSCs group showed significant difference in disc height index compared to the BMDMSCs group at both Co6-7 (93.7% ± 1.5% vs. 84.8% ± 1.0%, p = 0.011) and Co8-9 (86.0% ± 2.1% vs. 81.8% ± 1.7%, p = 0.012). In Baculo-BMP-7-BMDMSCs group, the zero-week treatment subgroup showed significant better in disc height index compared to two-week treatment group (p = 0.044), and four-week treatment group (p = 0.011). The zero-week treatment subgroup in Baculo-BMP-7-BMDMSCs group also had significant lower histology score than two-week treatment (4.3 vs. 5.7, p = 0.045) and four-week treatment (4.3 vs. 6.0, p = 0.031). In conclusion, Baculo-BMP-7-BMDMSC can slow down the progression of disc

  9. Co-culture of bone marrow-derived mesenchymal stem cells overexpressing lipocalin 2 with HK-2 and HEK293 cells protects the kidney cells against cisplatin-induced injury.

    PubMed

    Halabian, Raheleh; Roudkenar, Mehryar Habibi; Jahanian-Najafabadi, Ali; Hosseini, Kamran Mousavi; Tehrani, Hossein Abdul

    2015-02-01

    Conditioned medium of mesenchymal stem cells (MSCs) is now being used for its cytoprotective effects, especially when the cells are equipped with cytoprotective factors to strengthen them against unfavorable microenvironments. Overexpression of Lcn2 in MSCs mimics in vivo kidney injury. Hence, unraveling how Lcn2-engineered MSCs affect kidney cells has been investigated. Cisplatin treated HK-2 or HEK293 kidney cells were co-cultivated with Lcn2 overexpressing MSCs in upper and lower chambers of transwell plates. Proliferation, apoptosis, and expression of growth factors and cytokines were assessed in the kidney cells. Co-cultivation with the MSCs-Lcn2 not only inhibited cisplatin-induced cytotoxicity in the HK-2 and HEK293 cells, but increased proliferation rate, prevented cisplatin-induced apoptosis, and increased expression of growth factors and the amount of antioxidants in the kidney cells. Thus Lcn2-engineered MSCs can ameliorate and repair injured kidney cells in vitro, which strongly suggests there are beneficial effects of the MSCs-Lcn2 in cell therapy of kidney injury.

  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. EZH2 is overexpressed in laryngeal squamous cell carcinoma and enhances the stem-like properties of AMC-HN-8 cells

    PubMed Central

    Huang, Jiameng; Zhou, Liang; Chen, Hui; Wu, Chunping; Duo, Zhang; Zhang, Yanping

    2016-01-01

    The enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) histone methyltransferase is the catalytic subunit of polycomb repressive complex 2 (PRC2), which is important for epigenetic regulation. EZH2 is highly expressed in various types of tumors, and its high-level expression promotes the progression and invasion of certain tumors. However, the expression level of EZH2 and its functions in laryngeal squamous cell carcinomas are unknown. In the present study, the level of EZH2 expression in laryngeal squamous cell carcinomas was evaluated using immunochemical staining and reverse transcription-quantitative polymerase chain reaction. EZH2 was overexpressed in AMC-HN-8 cells with lentiviral transfection. Cell proliferation, apoptosis, cell-cycle, chemotherapy-sensitivity and in vivo tumorigenic assays were performed. The results indicated that EZH2 was highly expressed in laryngeal squamous cell carcinomas. Additionally, EZH2 overexpression promoted proliferation, accelerated cell-cycle progression and enhanced the tumorigenicity in laryngeal squamous cancer cells. More importantly, EZH2 enhanced the chemotherapy resistance of these cells. Overall, the results indicated that EZH2 promotes the progression of laryngeal squamous cell cancer and could be a potential chemotherapeutic target for the treatment of such cancer. PMID:27446358

  13. Curcumin Veto the Effects of Osteopontin (OPN) Specific Inhibitor on Leukemic Stem Cell Colony Forming Potential via Promotion of OPN Overexpression

    PubMed Central

    Mohammadi, Saeed; Ghaffari, Seyed H.; Shaiegan, Mojgan; Nikogoftar Zarif, Mahin; Nikbakht, Mohsen; Alimoghaddam, Kamran; Ghavamzadeh, Ardeshir

    2016-01-01

    Background: Acute myeloid leukemia (AML) is an immunophenotypically heterogeneous malignant disease, in which CD34 positivity is associated with poor prognosis. Osteopontin (OPN) plays different roles in physiologic and pathologic conditions like: survival, metastasis and cell protection from cytotoxic and apoptotic stimuli. Due to anti-apoptotic effect of OPN in normal and malignant cells, silencing of OPN leads to elevation of sensitivity towards chemotherapeutic agents and attenuates cancer cells migration and invasion. Therefore, the aim of this study was to evaluate OPN roles in modulating curcumin-mediated growth inhibitory on leukemic stem cells (LSCs) colony forming potential and survival in AML cell lines and primary CD34+/CD38- bone marrow-derived AML cells. Materials and Methods: Primary human CD34+/CD38- cells were isolated from bone marrow mononuclear cells of 10 AML patients at initial state of diagnosis, using a CD34 Multi sort kit. The growth inhibitory effects of curcumin (CUR) were evaluated by MTT and colony-formation assays. Apoptosis was analyzed by 7AAD assay in CD34+ KG-1, U937 cell lines and primary isolated cells. Short interfering RNA (siRNA) against OPN was used for OPN silencing in both cell lines and primary AML cells. Then, transfected cells were incubated with/without curcumin. The change in OPN gene expression was examined by Real-time PCR. Results: CUR inhibited proliferation and induced apoptosis in both KG-1 and U937 cells and also primary isolated AML cells. OPN silencing by siRNA increased the susceptibility of KG-1, U937 and primary CD34+/CD38- AML cells to apoptosis. Moreover, soft agar colony assays revealed that silencing of OPN with siRNA significantly decreased colony numbers in LSCs compared with the non-targeting group. Furthermore, CD34+/CD38- populations as a main LSCs compartment through OPN overexpression towards CUR treatment might be nullified the inhibitory effects of OPN siRNA on their survival and colony forming

  14. Therapeutic effects of the transplantation of VEGF overexpressing bone marrow mesenchymal stem cells in the hippocampus of murine model of Alzheimer’s disease

    PubMed Central

    Garcia, Karina O.; Ornellas, Felipe L. M.; Martin, Priscila K. Matsumoto; Patti, Camilla L.; Mello, Luiz E.; Frussa-Filho, Roberto; Han, Sang W.; Longo, Beatriz M.

    2014-01-01

    Alzheimer’s disease (AD) is clinically characterized by progressive memory loss, behavioral and learning dysfunction and cognitive deficits, such as alterations in social interactions. The major pathological features of AD are the formation of senile plaques and neurofibrillary tangles together with neuronal and vascular damage. The double transgenic mouse model of AD (2xTg-AD) with the APPswe/PS1dE9 mutations shows characteristics that are similar to those observed in AD patients, including social memory impairment, senile plaque formation and vascular deficits. Mesenchymal stem cells (MSCs), when transplanted into the brain, produce positive effects by reducing amyloid-beta (Aβ) deposition in transgenic amyloid precursor protein (APP)/presenilins1 (PS1) mice. Vascular endothelial growth factor (VEGF), exhibits neuroprotective effects against the excitotoxicity implicated in the AD neurodegeneration. The present study investigates the effects of MSCs overexpressing VEGF in hippocampal neovascularization, cognitive dysfunction and senile plaques present in 2xTg-AD transgenic mice. MSC were transfected with vascular endothelial growth factor cloned in uP vector under control of modified CMV promoter (uP-VEGF) vector, by electroporation and expanded at the 14th passage. 2xTg-AD animals at 6, 9 and 12 months old were transplanted with MSC-VEGF or MSC. The animals were tested for behavioral tasks to access locomotion, novelty exploration, learning and memory, and their brains were analyzed by immunohistochemistry (IHC) for vascularization and Aβ plaques. MSC-VEGF treatment favored the neovascularization and diminished senile plaques in hippocampal specific layers. Consequently, the treatment was able to provide behavioral benefits and reduce cognitive deficits by recovering the innate interest to novelty and counteracting memory deficits present in these AD transgenic animals. Therefore, this study has important therapeutic implications for the vascular damage in

  15. Direct induction of hepatocyte-like cells from immortalized human bone marrow mesenchymal stem cells by overexpression of HNF4α.

    PubMed

    Hu, Xiaojun; Xie, Peiyi; Li, Weiqiang; Li, Zhengran; Shan, Hong

    2016-09-16

    Hepatocytes from human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are expected to be a useful source for cell transplantation. However, relatively low efficiency and repeatability of hepatic differentiation of human BM-MSCs remains an obstacle for clinical translation. Hepatocyte nuclear factor 4 alpha (HNF4α), a critical transcription factor, plays an essential role in the entire process of liver development. In this study, immortalized hBM-MSCs, UE7T-13 cells were transduced with a lentiviral vector containing HNF4α. The typical fibroblast-like morphology of the MSCs changed, and polygonal, epithelioid cells grew out after HNF4α transduction. In hepatocyte culture medium, HNF4α-transduced MSCs (E7-hHNF4α cells) strongly expressed the albumin (ALB), CYP2B6, alpha-1 antitrypsin (AAT), and FOXA2 mRNA and exhibited morphology markedly similar to that of mature hepatocytes. The E7-hHNF4α cells showed hepatic functions such as Indocyanine green (ICG) uptake and release, glycogen storage, urea production and ALB secretion. Approximately 28% of E7-hHNF4α cells expressed both ALB and AAT. Furthermore, these E7-hHNF4α cells via superior mesenteric vein (SMV) injection expressed human ALB in mouse chronic injured liver. In conclusion, this study represents a novel strategy by directly inducing hepatocyte-like cells from MSCs. PMID:27501760

  16. MicroRNA-143 is a critical regulator of cell cycle activity in stem cells with co-overexpression of Akt and angiopoietin-1 via transcriptional regulation of Erk5/cyclin D1 signaling

    PubMed Central

    Lai, Vien Khach; Ashraf, Muhammad; Jiang, Shujia

    2012-01-01

    We report that simultaneous expression of Akt and angiopoietin-1 (Ang-1) transgenes supported mitogenesis in stem cells with a critical role for microRNA-143 (miR-143) downstream of FoxO1 transcription factor. Mesenchymal stem cells (MSC) from young male rats were transduced with Ad-vectors encoding for Akt (AktMSC) and Ang-1 (Ang-1MSC) transgenes for their individual or simultaneous overexpression (AAMSC; > 5-fold gene level and > 4-fold Akt and Ang-1 protein expression in AAMSC vs. Ad-Empty transduced MSC; EmpMSC). AAMSC had higher phosphorylation of FoxO1, which activated Erk5, a distinct mitogen-induced MAPK that drove transcriptional activation of cyclin D1 and Cdk4. Flow cytometry showed > 10% higher S-phase cell population that was confirmed by BrdU assay (15%) and immunohistology for Ki67 (11%) in AAMSC using EmpMSC as controls. miR array supported by real-time PCR showed induction of miR-143 in AAMSC (4.73-fold vs. EmpMSC). Luciferase assay indicated a dependent relationship between miR-143 and Erk5 in AAMSC. FoxO1-specific siRNA upregulated miR-143, whereas inhibition of miR-143 did not change FoxO1 activation. However, miR-143 inhibition repressed phosphorylation of Erk5 and abrogated cyclin D1 with concomitant reduction in cells entering cell cycle. During in vivo studies, male GFP+ AAMSC transplanted into wild-type female infarcted rat hearts showed significantly higher numbers of Ki67-expressing cells (p < 0.05 vs. EmpMSC) 7 d after engraftment (n = 4 animals/group). In conclusion, co-overexpression of Akt and Ang-1 in MSC activated cell cycle progression by upregulation of miR-143 and stimulation of FoxO1 and Erk5 signaling. PMID:22374674

  17. Overexpression of cellular repressor of E1A-stimulated genes inhibits TNF-{alpha}-induced apoptosis via NF-{kappa}B in mesenchymal stem cells

    SciTech Connect

    Peng, Cheng-Fei; Han, Ya-Ling; Jie-Deng,; Yan, Cheng-Hui; Jian-Kang,; Bo-Luan,; Jie-Li

    2011-03-25

    Research highlights: {yields} CREG protected MSCs from tumor necrosis factor-{alpha} (TNF-{alpha}) induced apoptosis. {yields} CREG inhibits the phosphorylation of I{kappa}B{alpha} and prevents the activation of NF-{kappa}B. {yields} CREG inhibits NF-{kappa}B nuclear translocation and pro-apoptosis protein transcription. {yields} CREG anti-apoptotic effect involves inhibition of the death receptor pathway. {yields} p53 is downregulated by CREG via NF-{kappa}B pathway under TNF-{alpha} stimulation. -- Abstract: Bone marrow-derived mesenchymal stem cells (MSCs) show great potential for therapeutic repair after myocardial infarction. However, poor viability of transplanted MSCs in the ischemic heart has limited their use. Cellular repressor of E1A-stimulated genes (CREG) has been identified as a potent inhibitor of apoptosis. This study therefore aimed to determine if rat bone marrow MSCs transfected with CREG-were able to effectively resist apoptosis induced by inflammatory mediators, and to demonstrate the mechanism of CREG action. Apoptosis was determined by flow cytometric and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling assays. The pathways mediating these apoptotic effects were investigated by Western blotting. Overexpression of CREG markedly protected MSCs from tumor necrosis factor-{alpha} (TNF-{alpha}) induced apoptosis by 50% after 10 h, through inhibition of the death-receptor-mediated apoptotic pathway, leading to attenuation of caspase-8 and caspase-3. Moreover, CREG resisted the serine phosphorylation of I{kappa}B{alpha} and prevented the nuclear translocation of the transcription factor nuclear factor-{kappa}B (NF-{kappa}B) under TNF-{alpha} stimulation. Treatment of cells with the NF-{kappa}B inhibitor pyrrolidine dithiocarbamate (PDTC) significantly increased the transcription of pro-apoptosis proteins (p53 and Fas) by NF-{kappa}B, and attenuated the anti-apoptotic effects of CREG on MSCs. The results of this study

  18. Drosophila's contribution to stem cell research

    PubMed Central

    Singh, Gyanesh

    2016-01-01

    The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila. PMID:26180635

  19. Drosophila's contribution to stem cell research.

    PubMed

    Singh, Gyanesh

    2015-01-01

    The discovery of Drosophila stem cells with striking similarities to mammalian stem cells has brought new hope for stem cell research. Recent developments in Drosophila stem cell research is bringing wider opportunities for contemporary stem cell biologists. In this regard, Drosophila germ cells are becoming a popular model of stem cell research. In several cases, genes that controlled Drosophila stem cells were later discovered to have functional homologs in mammalian stem cells. Like mammals, Drosophila germline stem cells (GSCs) are controlled by both intrinsic as well as external signals. Inside the Drosophila testes, germline and somatic stem cells form a cluster of cells (the hub). Hub cells depend on JAK-STAT signaling, and, in absence of this signal, they do not self-renew. In Drosophila, significant changes occur within the stem cell niche that contributes to a decline in stem cell number over time. In case of aging Drosophila, somatic niche cells show reduced DE-cadherin and unpaired (Upd) proteins. Unpaired proteins are known to directly decrease stem cell number within the niches, and, overexpression of upd within niche cells restored GSCs in older males also . Stem cells in the midgut of Drosophila are also very promising. Reduced Notch signaling was found to increase the number of midgut progenitor cells. On the other hand, activation of the Notch pathway decreased proliferation of these cells. Further research in this area should lead to the discovery of additional factors that regulate stem and progenitor cells in Drosophila. PMID:26180635

  20. Encapsulation of bone morphogenic protein-2 with Cbfa1-overexpressing osteogenic cells derived from human embryonic stem cells in hydrogel accelerates bone tissue regeneration.

    PubMed

    Kim, Min Jung; Park, Ji Sun; Kim, Sinae; Moon, Sung-Hwan; Yang, Han Na; Park, Keun-Hong; Chung, Hyung-Min

    2011-08-01

    Bone tissue defects caused by trauma and disease are significant problems in orthopedic surgery. Human embryonic stem cells (hESCs) hold great promise for the treatment of bone tissue disease in regenerative medicine. In this study, we have established an effective method for the differentiation of osteogenic cells derived from hESCs using a lentiviral vector containing the transcription factor Cbfa1. Differentiation was initiated in embryoid body formation of Cbfa1-expressing hESCs, resulting in a highly purified population of osteogenic cells based on flow cytometric analysis. These cells also showed characteristics of osteogenic cells in vitro, as determined by reverse-transcription (RT)-polymerase chain reaction and immunocytochemistry using osteoblast-specific markers. We also evaluated the regenerative potential of Cbfa1-expressing cells derived from hESCs (hESC-CECs) compared with hESCs and the osteogenic effects of bone morphogenic protein-2 (BMP2) encapsulated in thermoreversible hydrogel in vivo. hESC-CECs were embedded in hydrogel constructs enriched with BMP2 to promote bone regeneration. We observed prominent mineralization and the formation of nodule-like structures using von Kossa and alizarin red S staining. In addition, the expression patterns of osteoblast-specific genes were verified by RT-polymerase chain reaction, and immunohistochemical analysis revealed that collagen type 1 and Cbfa1 were highly expressed in hESC-CECs compared with other cell types. Taken together, our results suggest that encapsulation of hESC-CECs with BMP2 in hydrogel constructs appears to be a promising method to enhance the in vitro osteoblastic differentiation and in vivo osteogenic activity of hESC-CECs.

  1. Stem Cell Sciences plc.

    PubMed

    Daniels, Sebnem

    2006-09-01

    Stem Cell Sciences' core objective is to develop safe and effective stem cell-based therapies for currently incurable diseases. In order to achieve this goal, Stem Cell Sciences recognizes the need for multiple technologies and a globally integrated stem cell initiative. The key challenges for the successful application of stem cells in the clinic is the need for a reproducible supply of pure, fully characterized stem cells that have been grown in suitable conditions for use in the clinic.

  2. Transplantation of adipose tissue-derived stem cells overexpressing heme oxygenase-1 improves functions and remodeling of infarcted myocardium in rabbits.

    PubMed

    Yang, Jun-jie; Yang, Xia; Liu, Zhi-qiang; Hu, Shun-yin; Du, Zhi-yan; Feng, Lan-lan; Liu, Jian-feng; Chen, Yun-dai

    2012-01-01

    Adipose tissue-derived stem cells (ADSCs) are a promising source of autologous stem cells that are used for regeneration and repair of infracted heart. However, the efficiency of their transplantation is under debate. One of the possible reasons for marginal improvement in ADSCs transplantation is the significant cell death rate of implanted cells after being grafted into injured heart. Therefore, overcoming the poor survival rate of implanted cells may improve stem cell therapy. Due to limited improvement concerning direct stem cell therapy, gene-transfer methods are used to enhance cellular cardiomyoplasty efficacy. Heme oxygenase-1 (HO-1) can provide various types of cells with protection against oxidative injury and apoptosis. However, exact effects of autologous ADSCs combined with HO-1 on cardiac performance remains unknown. In this study, rabbits were treated with ADSCs transduced with HO-1 (HO-1-ADSCs), treated with non-transduced ADSCs, or injected with phosphate buffered saline 14 days after experimental myocardial infarction was induced, when autologous ADSCs were obtained simultaneously. Four weeks after injection, echocardiography showed significant improvements for cardiac functions and left ventricular dimensions in HO-1-ADSCs-treated animals. Structural consequences of transplantation were determined by detailed histological analysis, which showed differentiation of HO-1-ADSCs to cardiomyocyte-like tissues and lumen-like structure organizations. Apart from improvement in angiogenesis and scar areas, more connexin 43-positive gap junction and greater tyrosine hydroxylase-positive cardiac sympathetic nerves sprouting were observed in the HO-1-ADSCs-treated group compared with ADSCs group. These data suggest that the transplantation of autologous ADSCs combined with HO-1 transduction is a feasible and efficacious method for improving infarcted myocardium.

  3. Adult Stem and Progenitor Cells

    NASA Astrophysics Data System (ADS)

    Geraerts, Martine; Verfaillie, Catherine M.

    The discovery of adult stem cells in most adult tissues is the basis of a number of clinical studies that are carried out, with therapeutic use of hematopoietic stem cells as a prime example. Intense scientific debate is still ongoing as to whether adult stem cells may have a greater plasticity than previously thought. Although cells with some features of embryonic stem cells that, among others, express Oct4, Nanog and SSEA1 are isolated from fresh tissue, it is not clear if the greater differentiation potential is acquired during cell culture. Moreover, adult more pluripotent cells do not have all pluripotent characteristics typical for embryonic stem cells. Recently, some elegant studies were published in which adult cells could be completely reprogrammed to embryonic stem cell-like cells by overexpression of some key transcription factors for pluripotency (Oct4, Sox2, Klf4 and c-Myc). It will be interesting for the future to investigate the exact mechanisms underlying this reprogramming and whether similar transcription factor pathways are present and/or can be activated in adult more pluripotent stem cells.

  4. 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

  5. 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

  6. Overexpression of a pectin methylesterase inhibitor in Arabidopsis thaliana leads to altered growth morphology of the stem and defective organ separation

    PubMed Central

    Müller, Kerstin; Levesque-Tremblay, Gabriel; Fernandes, Anwesha; Wormit, Alexandra; Bartels, Sebastian; Usadel, Bjoern; Kermode, Allison

    2013-01-01

    The methylesterification status of cell wall pectins, mediated through the interplay of pectin methylesterases (PMEs) and pectin methylesterase inhibitors (PMEIs), influences the biophysical properties of plant cell walls. We found that the overexpression of a PMEI gene in Arabidopsis thaliana plants caused the stems to develop twists and loops, most strongly around points on the stem where leaves or inflorescences failed to separate from the main stem. Altered elasticity of the stem, underdevelopment of the leaf cuticle, and changes in the sugar composition of the cell walls of stems were evident in the PMEI overexpression lines. We discuss the mechanisms that potentially underlie the aberrant growth phenotypes. PMID:24675171

  7. Overexpression of β-NGF promotes differentiation of bone marrow mesenchymal stem cells into neurons through regulation of AKT and MAPK pathway.

    PubMed

    Yuan, Jun; Huang, Guorong; Xiao, Zhe; Lin, Lvbiao; Han, Tianwang

    2013-11-01

    Bone marrow stromal stem cells (BMSCs) are fibroblastic in shape and capable of self-renewal and have the potential for multi-directional differentiation. Nerve growth factor (NGF), a homodimeric polypeptide, plays an important role in the nervous system by supporting the survival and growth of neural cells, regulating cell growth, promoting differentiation into neuron, and neuron migration. Adenoviral vectors are DNA viruses that contain 36 kb of double-stranded DNA allowing for transmission of the genes to the host nucleus but not inserting them into the host chromosome. The present study aimed to investigate the induction efficiency and differentiation of neural cells from BMSCs by β-NGF gene transfection with recombinant adenoviral vector (Ad-β-NGF) in vitro. The results of immunochemical assay confirmed the induced cells as neuron cells. Moreover, flow cytometric analysis, Annexin-V-FITC/PI, and BrdU assay revealed that chemical inducer β-mercaptoethanol (β-met) triggered apoptosis of BMSCs, as evidenced by inhibition of DNA fragmentation, nuclear condensation, translocation of phospholipid phosphatidylserine, and activation of caspase-3. Furthermore, the results of western blotting showed that β-met suppressed AKT signaling pathway and regulated the MAPKs during differentiation of BMSCs. In contrast, Ad-β-NGF effectively induced the differentiation of BMSCs without causing any cytopathic phenomenon and apoptotic cell death. Moreover, Ad-β-NGF recovered the expression level of phosphorylated AKT and MAPKs in cells exposed to chemical reagents. Taken together, these results suggest that β-NGF gene transfection promotes the differentiation of BMSCs into neurons through regulation of AKT and MAPKs signaling pathways. PMID:23934089

  8. Overexpression of two cambium-abundant Chinese fir (Cunninghamia lanceolata) α-expansin genes ClEXPA1 and ClEXPA2 affect growth and development in transgenic tobacco and increase the amount of cellulose in stem cell walls.

    PubMed

    Wang, Guifeng; Gao, Yan; Wang, Jinjun; Yang, Liwei; Song, Rentao; Li, Xiaorong; Shi, Jisen

    2011-05-01

    Expansins are unique plant cell wall proteins that possess the ability to induce immediately cell wall extension in vitro and cell expansion in vivo. To investigate the biological functions of expansins that are abundant in wood-forming tissues, we cloned two expansin genes from the differentiating xylem of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook). Phylogenetic reconstruction indicated that they belong to α-expansin (EXPA), named ClEXPA1 and ClEXPA2. Expression pattern analysis demonstrated that they are preferentially expressed in the cambium region. Overexpression of ClEXPA1 and ClEXPA2 in tobacco plants yielded pleiotropic phenotypes of plant height, stem diameter, leaf number and seed pod. The height and diameter growth of the 35S(pro) :ClEXPA1 and 35S(pro) :ClEXPA2 transgenic plants were increased drastically, exhibiting an enlargement of pith parenchyma cell size. Isolated cell walls of ClEXPA1 and ClEXPA2 overexpressors contained 30%-50% higher cellulose contents than the wild type, accompanied by a thickening of the cell walls in the xylem region. Both ClEXPA1 and ClEXPA2 are involved in plant growth and development, with a partially functional overlap. Expansins are not only able to induce cell expansion in different tissues/organs in vivo, but they also can act as a potential activator during secondary wall formation by directly or indirectly affecting cellulose metabolism, probably in a cell type-dependent manner.

  9. Treatment of Parkinson disease with C17.2 neural stem cells overexpressing NURR1 with a recombined republic-deficit adenovirus containing the NURR1 gene.

    PubMed

    Li, Qing-Jun; Tang, Ya-Mei; Liu, Jun; Zhou, Dao-You; Li, Xiang-Pen; Xiao, Song-Hua; Jian, Dong-Xing; Xing, Yi-Gang

    2007-12-01

    To study the potential benefit of the NURR1 gene in Parkinson's disease (PD), we constructed a recombinant republic-deficit adenovirus containing the NURR1 gene (Ad-NURR1) and expressed it in transplanted neural stem cells (NSC). Ad-NURR1 was constructed, and NURR1 mRNA and protein expression were identified by in situ hybridization and western blot analysis, respectively. The identified NURR1 protein could directly or indirectly induce NSC differentiation into neurons. To identify a potential therapeutic use for the transfected NSCs, cells were transplanted into 6-hydroxydopamine lesioned rats. Histopathological and behavioral alterations were evaluated via immunohistochemistry and the ration test, respectively, in rats transplanted with NSCs with or without the Ad-NURR1 adenovirus. The Ad-NURR1 construct effectively expressed the NURR1 protein, which could directly or indirectly induce NSC differentiation into neurons. Both histopathological and behavioral alterations were seen in rats treated with NSCs with or without the Ad-NURR1 construct, although in the case of the latter, the benefits were more robust. These results suggest a potential therapeutic benefit for Ad-NURR1-expressing cells in the treatment of PD. The Ad-NURR1 modification induced NSC differentiation and therefore represents a potential therapy for PD.

  10. Interaction between amiodarone and hepatitis-C virus nucleotide inhibitors in human induced pluripotent stem cell-derived cardiomyocytes and HEK-293 Cav1.2 over-expressing cells.

    PubMed

    Lagrutta, Armando; Zeng, Haoyu; Imredy, John; Balasubramanian, Bharathi; Dech, Spencer; Lis, Edward; Wang, Jixin; Zhai, Jin; DeGeorge, Joseph; Sannajust, Frederick

    2016-10-01

    Several clinical cases of severe bradyarrhythmias have been reported upon co-administration of the Hepatitis-C NS5B Nucleotide Polymerase Inhibitor (HCV-NI) direct-acting antiviral agent, sofosbuvir (SOF), and the Class-III anti-arrhythmic amiodarone (AMIO). We model the cardiac drug-drug interaction (DDI) between AMIO and SOF, and between AMIO and a closely-related SOF analog, MNI-1 (Merck Nucleotide Inhibitor #1), in functional assays of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), to provide mechanistic insights into recently reported clinical cases. AMIO co-applied with SOF or MNI-1 increased beating rate or field potential (FP) rate and decreased impedance (IMP) and Ca(2+) transient amplitudes in hiPSC-CM syncytia. This action resembled that of Ca(2+) channel blockers (CCBs) in the model, but CCBs did not substitute for AMIO in the DDI. AMIO analog dronedarone (DRON) did not substitute for, but competed with AMIO in the DDI. Ryanodine and thapsigargin, decreasing intracellular Ca(2+) stores, and SEA-0400, a Na(+)/Ca(2+) exchanger-1 (NCX1) inhibitor, partially antagonized or suppressed DDI effects. Other agents affecting FP rate only exerted additive or subtractive effects, commensurate with their individual effects. We also describe an interaction between AMIO and MNI-1 on Cav1.2 ion channels in an over-expressing HEK-293 cell line. MNI-1 enhanced Cav1.2 channel inhibition by AMIO, but did not affect inhibition of Cav1.2 by DRON, verapamil, nifedipine, or diltiazem. Our data in hiPSC-CMs indicate that HCV-NI agents such as SOF and MNI-1 interact with key intracellular Ca(2+)-handling mechanisms. Additional study in a Cav1.2 HEK-293 cell-line suggests that HCV-NIs potentiate the inhibitory action of AMIO on L-type Ca(2+) channels.

  11. 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.

  12. 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 ...

  13. 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.

  14. Artificial Stem Cell Niches

    PubMed Central

    Lutolf, Matthias P.; Blau, Helen M.

    2011-01-01

    Stem cells are characterized by their dual ability to reproduce themselves (self-renew) and specialize (differentiate), yielding a plethora of daughter cells that maintain and regenerate tissues. In contrast to their embryonic counterparts, adult stem cells retain their unique functions only if they are in intimate contact with an instructive microenvironment, termed stem cell niche. In these niches, stem cells integrate a complex array of molecular signals that, in concert with induced cell-intrinsic regulatory networks, control their function and balance their numbers in response to physiologic demands. This progress report provides a perspective on how advanced materials technologies could be used (i) to engineer and systematically analyze specific aspects of functional stem cells niches in a controlled fashion in vitro and (ii) to target stem cell niches in vivo. Such “artificial niches” constitute potent tools for elucidating stem cell regulatory mechanisms with the capacity to directly impact the development of novel therapeutic strategies for tissue regeneration. PMID:20882496

  15. Development and Gene Expression of Porcine Cloned Embryos Derived from Bone Marrow Stem Cells with Overexpressing Oct4 and Sox2

    PubMed Central

    Lee, Jeong-Hyeon; Lee, Won-Jae; Jeon, Ryoung-Hoon; Lee, Yeon-Mi; Jang, Si-Jung; Lee, Sung-Lim; Jeon, Byung-Geun; Ock, Sun-A; King, W. Allen

    2014-01-01

    Abstract The present study compared the potential of porcine bone marrow mesenchymal stem cells (pBMSCs) at different passages as nuclear transfer (NT) donors and the developmental efficiency of NT embryos from donor cells transfected with/without Oct4 and Sox2. Early-passage pBMSCs showed higher proliferation and expression of Oct4 and Sox2 and differentiation potential into mesenchymal lineages than middle- and late-passage pBMSCs. Cleavage rate did not differ among pBMSCs at different passages, but NT embryos with early-passage pBMSCs and middle-passage pBMSCs transfected with Oct4 (Oct4-pBMSCs) had significantly (p<0.05) higher blastocyst development than those with middle-passage pBMSCs. The incidence of apoptotic bodies in NT blastocysts from late-passage pBMSCs and Sox2-transfected middle-passage pBMSCs (Sox2-pBMSCs) was significantly (p<0.05) higher than others. The transcriptional levels of Oct4, Sox2, Nanog, Cdx2, Dnmt3a, and Igf2r genes were significantly (p<0.05) higher in Oct4- and Sox2-pBMSCs NT embryos. Middle-passage pBMSCs NT embryos revealed lower transcriptional levels of Bcl2 than others, except Sox2-pBMSCs NT embryos. The transcriptional level of Bax increased gradually in NT embryos derived from pBMSCs following extended passages and was significantly (p<0.05) higher in Sox2-pBMSCs NT embryos. Our results demonstrated that early-passage pBMSCs are more potent in expressing transcription factors and displayed higher differentiation ability, and middle-passage pBMSCs transfected with Oct4 improved the developmental efficiency of NT embryos, suggesting that high Oct4 expression cells are more efficient as NT donors. PMID:25437870

  16. Stem cell applications in diabetes.

    PubMed

    Noguchi, Hirofumi

    2012-01-01

    Diabetes mellitus is a devastating disease and the World Health Organization (WHO) expects that the number of diabetic patients will increase to 300 million by the year 2025. Patients with diabetes experience decreased insulin secretion that is linked to a significant reduction in the number of islet cells. Type 1 diabetes is characterized by the selective destruction of pancreatic β cells caused by an autoimmune attack. Type 2 diabetes is a more complex pathology that, in addition to β cell loss caused by apoptotic programs, includes β cell de-differentiation and peripheric insulin resistance. The success achieved over the last few years with islet transplantation suggests that diabetes can be cured by the replenishment of deficient β cells. These observations are proof of the concept and have intensified interest in treating diabetes or other diseases not only by cell transplantation but also by stem cells. An increasing body of evidence indicates that, in addition to embryonic stem cells, several potential adult stem/progenitor cells derived from the pancreas, liver, spleen, and bone marrow could differentiate into insulin-producing cells in vitro or in vivo. However, significant controversy currently exists in this field. Pharmacological approaches aimed at stimulating the in vivo/ex vivo regeneration of β cells have been proposed as a way of augmenting islet cell mass. Overexpression of embryonic transcription factors in stem cells could efficiently induce their differentiation into insulin-expressing cells. A new technology, known as protein transduction, facilitates the differentiation of stem cells into insulin-producing cells. Recent progress in the search for new sources of β cells has opened up several possibilities for the development of new treatments for diabetes.

  17. 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) ...

  18. Combined Overexpression of JARID2, PRDM14, ESRRB, and SALL4A Dramatically Improves Efficiency and Kinetics of Reprogramming to Induced Pluripotent Stem Cells.

    PubMed

    Iseki, Hiroyoshi; Nakachi, Yutaka; Hishida, Tomoaki; Yamashita-Sugahara, Yzumi; Hirasaki, Masataka; Ueda, Atsushi; Tanimoto, Yoko; Iijima, Saori; Sugiyama, Fumihiro; Yagami, Ken-ichi; Takahashi, Satoru; Okuda, Akihiko; Okazaki, Yasushi

    2016-02-01

    Identification of a gene set capable of driving rapid and proper reprogramming to induced pluripotent stem cells (iPSCs) is an important issue. Here we show that the efficiency and kinetics of iPSC reprogramming are dramatically improved by the combined expression of Jarid2 and genes encoding its associated proteins. We demonstrate that forced expression of JARID2 promotes iPSC reprogramming by suppressing the expression of Arf, a known reprogramming barrier, and that the N-terminal half of JARID2 is sufficient for such promotion. Moreover, JARID2 accelerated silencing of the retroviral Klf4 transgene and demethylation of the Nanog promoter, underpinning the potentiating activity of JARID2 in iPSC reprogramming. We further show that JARID2 physically interacts with ESRRB, SALL4A, and PRDM14, and that these JARID2-associated proteins synergistically and robustly facilitate iPSC reprogramming in a JARID2-dependent manner. Our findings provide an insight into the important roles of JARID2 during reprogramming and suggest that the JARID2-associated protein network contributes to overcoming reprogramming barriers.

  19. Transition metals activate TFEB in overexpressing cells.

    PubMed

    Peña, Karina A; Kiselyov, Kirill

    2015-08-15

    Transition metal toxicity is an important factor in the pathogenesis of numerous human disorders, including neurodegenerative diseases. Lysosomes have emerged as important factors in transition metal toxicity because they handle transition metals via endocytosis, autophagy, absorption from the cytoplasm and exocytosis. Transcription factor EB (TFEB) regulates lysosomal biogenesis and the expression of lysosomal proteins in response to lysosomal and/or metabolic stresses. Since transition metals cause lysosomal dysfunction, we proposed that TFEB may be activated to drive gene expression in response to transition metal exposure and that such activation may influence transition metal toxicity. We found that transition metals copper (Cu) and iron (Fe) activate recombinant TFEB and stimulate the expression of TFEB-dependent genes in TFEB-overexpressing cells. In cells that show robust lysosomal exocytosis, TFEB was cytoprotective at moderate levels of Cu exposure, decreasing oxidative stress as reported by the expression of heme oxygenase-1 (HMOX1) gene. However, at high levels of Cu exposure, particularly in cells with low levels of lysosomal exocytosis, activation of overexpressed TFEB was toxic, increasing oxidative stress and mitochondrial damage. Based on these data, we conclude that TFEB-driven gene network is a component of the cellular response to transition metals. These data suggest limitations and disadvantages of TFEB overexpression as a therapeutic approach. PMID:26251447

  20. Transition metals activate TFEB in overexpressing cells

    PubMed Central

    Peña, Karina A.; Kiselyov, Kirill

    2015-01-01

    Transition metal toxicity is an important factor in the pathogenesis of numerous human disorders, including neurodegenerative diseases. Lysosomes have emerged as important factors in transition metal toxicity because they handle transition metals via endocytosis, autophagy, absorption from the cytoplasm and exocytosis. Transcription factor EB (TFEB) regulates lysosomal biogenesis and the expression of lysosomal proteins in response to lysosomal and/or metabolic stresses. Since transition metals cause lysosomal dysfunction, we proposed that TFEB may be activated to drive gene expression in response to transition metal exposure and that such activation may influence transition metal toxicity. We found that transition metals copper (Cu) and iron (Fe) activate recombinant TFEB and stimulate the expression of TFEB-dependent genes in TFEB-overexpressing cells. In cells that show robust lysosomal exocytosis, TFEB was cytoprotective at moderate levels of Cu exposure, decreasing oxidative stress as reported by the expression of heme oxygenase-1 (HMOX1) gene. However, at high levels of Cu exposure, particularly in cells with low levels of lysosomal exocytosis, activation of overexpressed TFEB was toxic, increasing oxidative stress and mitochondrial damage. Based on these data, we conclude that TFEB-driven gene network is a component of the cellular response to transition metals. These data suggest limitations and disadvantages of TFEB overexpression as a therapeutic approach. PMID:26251447

  1. PEDF & stem cells: niche vs. nurture.

    PubMed

    Fitchev, Philip; Chung, Chuhan; Plunkett, Beth A; Brendler, Charles B; Crawford, Susan E

    2014-01-01

    Anti-angiogenic pigment epithelium-derived factor (PEDF) is a multifunctional 50kD secreted glycoprotein emerging as a key factor in stem cell renewal. Characteristics of the stem cell niche can be highly dependent on location, access to the vasculature, oxygen tension and neighboring cells. In the neural stem cell (NSC) niche, specifically the subventricular zone, PEDF actively participates in the self renewal process and promotes stemness by upregulating Notch signaling effectors Hes1 and Hes5. The local vascular endothelial cells and ependymal cells are the likely sources of PEDF for the NSC while mesenchymal and retinal stem cells can actually produce PEDF. The opposing actions of PEDF and VEGF on various cells are recapitulated in the NSC niche. Intraventricular injection of PEDF promotes stem cell renewal, while injection of VEGF prompts differentiation and neurogenesis in the subventricular zone. Enhancing the expression of PEDF in stem cells has promising therapeutic implications. Bone marrow mesenchymal stem cells overexpressing PEDF effectively inhibited pathologic angiogenesis in the murine eye and these same cells suppressed hepatocellular carcinoma growth. As a protein with bioactivities in nearly all normal organ systems, it is likely that PEDF will continue to gain visibility as an essential component in the development and delivery of novel stem cell-based therapies to combat disease.

  2. Stem cells and reproduction

    PubMed Central

    Du, Hongling; Taylor, Hugh S.

    2011-01-01

    Purpose of review To review the latest developments in reproductive tract stem cell biology. Recent findings In 2004, two studies indicated that ovaries contain stem cells which form oocytes in adults and that can be cultured in vitro into mature oocytes. A live birth after orthotopic transplantation of cyropreserved ovarian tissue in a woman whose ovaries were damaged by chemotherapy demonstrates the clinical potential of these cells. In the same year, another study provided novel evidence of endometrial regeneration by stem cells in women who received bone marrow transplants. This finding has potential for the use in treatment of uterine disorders. It also supports a new theory for the cause of endometriosis, which may have its origin in ectopic transdifferentiation of stem cells. Several recent studies have demonstrated that fetal cells enter the maternal circulation and generate microchimerism in the mother. The uterus is a dynamic organ permeable to fetal stem cells, capable of transdifferentiation and an end organ in which bone marrow stem cells may differentiate. Finally stem cell transformation can be an underlying cause of ovarian cancer. Summary Whereas we are just beginning to understand stem cells, the potential implications of stem cells to reproductive biology and medicine are apparent. PMID:20305558

  3. Stem cells in urology.

    PubMed

    Aboushwareb, Tamer; Atala, Anthony

    2008-11-01

    The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem cell research. Instead, scientists have explored other cell sources, including progenitor and stem cells derived from adult tissues and stem cells derived from the amniotic fluid and placenta. In addition, novel techniques for generating stem cells in the laboratory are being developed. These techniques include somatic cell nuclear transfer, in which the nucleus of an adult somatic cell is placed into an oocyte, and reprogramming of adult cells to induce stem-cell-like behavior. Such techniques are now being used in tissue engineering applications, and some of the most successful experiments have been in the field of urology. Techniques to regenerate bladder tissue have reached the clinic, and exciting progress is being made in other areas, such as regeneration of the kidney and urethra. Cell therapy as a treatment for incontinence and infertility might soon become a reality. Physicians should be optimistic that regenerative medicine and tissue engineering will one day provide mainstream treatment options for urologic disorders.

  4. 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

  5. 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.

  6. Fish stem cell cultures.

    PubMed

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  7. Stem cells in dermatology.

    PubMed

    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.

  8. 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 ...

  9. 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

  10. 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...

  11. 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

  12. [Stem cells and cancer].

    PubMed

    Arvelo, Francisco; Cotte, Carlos; Sojo, Felipe

    2014-12-01

    Surgery, radiotherapy and chemotherapy are universally recognized as the most effective anti-cancer therapies. Despite significant advances directed towards elucidating molecular mechanisms and developing clinical trials, cancer still remains a major public health issue. Cancer stem cells are a subpopulation of the cells that form the tumor. The discovery of these human cancer cells opens a perspective for understanding tumor recurrence, drug resistance and metastasis; and opens up new research directions on how cancer cells are capable of switching from dormancy to malignancy. Therapeutic alternatives emerge from a better understanding of the biology and the environment of tumor stem cells. The present paper aims to summarize the characteristics and properties of cancer stem cells, the ongoing research, as well as the best strategies for prevention and control of the mechanisms of tumor recurrence.

  13. 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

  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. Stem cells in microfluidics

    PubMed Central

    Wu, Huei-Wen; Lin, Chun-Che; Lee, Gwo-Bin

    2011-01-01

    Microfluidic techniques have been recently developed for cell-based assays. In microfluidic systems, the objective is for these microenvironments to mimic in vivo surroundings. With advantageous characteristics such as optical transparency and the capability for automating protocols, different types of cells can be cultured, screened, and monitored in real time to systematically investigate their morphology and functions under well-controlled microenvironments in response to various stimuli. Recently, the study of stem cells using microfluidic platforms has attracted considerable interest. Even though stem cells have been studied extensively using bench-top systems, an understanding of their behavior in in vivo-like microenvironments which stimulate cell proliferation and differentiation is still lacking. In this paper, recent cell studies using microfluidic systems are first introduced. The various miniature systems for cell culture, sorting and isolation, and stimulation are then systematically reviewed. The main focus of this review is on papers published in recent years studying stem cells by using microfluidic technology. This review aims to provide experts in microfluidics an overview of various microfluidic systems for stem cell research. PMID:21522491

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. Breast cancer stem cells and radiation

    NASA Astrophysics Data System (ADS)

    Phillips, Tiffany Marie

    2007-12-01

    The present studies explore the response of breast cancer stem cells (BCSC's) to radiation and the implications for clinical cancer treatment. Current cancer therapy eliminates bulky tumor mass but may fail to eradicate a critical tumor initiating cell population termed "cancer stem cells". These cells are potentially responsible for tumor formation, metastasis, and recurrence. Recently cancer stem cells have been prospectively identified in various malignancies, including breast cancer. The breast cancer stem cell has been identified by the surface markers CD44+/CD24 -(low). In vitro mammosphere cultures allow for the enrichment of the cancer stem cell population and were utilized in order to study differential characteristics of BCSC's. Initial studies found that BCSC's display increased radiation resistance as compared to other non-stem tumor cells. This resistance was accompanied by decreased H2AX phosphorylation, decreased reactive oxygen species formation, and increased phosphorylation of the checkpoint protein Chk1. These studies suggest differential DNA damage and repair within the BCSC population. Studies then examined the consequences of fractionated radiation on the BCSC population and found a two-fold increase in BCSC's following 5 x 3Gy. This observation begins to tie cancer stem cell self-renewal to the clinical stem cell phenomenon of accelerated repopulation. Accelerated repopulation is observed when treatment gaps increase between sequential fractions of radiotherapy and may be due to cancer stem cell symmetric self-renewal. The balance between asymmetric and symmetric stem cell division is vital for proper maintenance; deregulation is likely linked to cancer initiation and progression. The developmental Notch-1 pathway was found to regulate BCSC division. Over-expressing the constitutively active Notch-1-ICD in MCF7 cells produced an increase in the BCSC population. Additionally, radiation was observed to increase the expression of the Notch-1

  1. Chemotherapy targeting cancer stem cells.

    PubMed

    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.

  2. 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

  3. Evaluation of In Vivo Osteogenic Potential of Bone Morphogenetic Protein 2-Overexpressing Human Periodontal Ligament Stem Cells Combined with Biphasic Calcium Phosphate Block Scaffolds in a Critical-Size Bone Defect Model.

    PubMed

    Yi, TacGhee; Jun, Choong-Man; Kim, Su Jin; Yun, Jeong-Ho

    2016-03-01

    Human periodontal ligament stem cells (hPDLSCs) are considered potential cellular carriers for gene delivery in the field of tissue regeneration. This study tested the osseoregenerative potential of hPDLSCs transduced with replication-deficient recombinant adenovirus (rAd) containing the gene encoding bone morphogenetic protein-2 (BMP2; hPDLSCs/rAd-BMP2) in both in vivo and in vitro osteogenic environments. After the optimal condition for rAd-mediated transduction was determined, hPDLSCs were transduced to express BMP2. In vivo bone formation was evaluated in a critical-size rat calvarial bone defect model that more closely mimics the harsher in vivo milieu for bone regeneration than subcutaneous transplantation model. As support materials for bone regeneration, block-type biphasic calcium phosphate (BCP) scaffolds were combined with hPDLSCs and/or BMP2 and transplanted into critical-size bone defects in rats. Experimental groups were as follows: BCP scaffold control (group 1 [Gr1]), scaffold containing recombinant human BMP2 (rhBMP2; group 2 [Gr2]), scaffold loaded with normal hPDLSCs (group 3 [Gr3]), scaffold combined with both normal hPDLSCs and rhBMP2 (group 4 [Gr4]), and scaffold loaded with hPDLSCs transduced with rAd-BMP2 (hPDLSCs/rAd-BMP2; group 5 [Gr5]). Our data showed that new bone formation was highest in Gr2. Less mineralization was observed in Gr3, Gr4, and Gr5 in which hPDLSCs were transplanted. In vitro transwell assay demonstrated that hPDLSCs exert an inhibitory activity on BMP2-induced osteogenic differentiation. Our findings suggest that the in vivo bone regenerative potential of BMP2-overexpressing hPDLSCs could be compromised in a critical-size rat calvarial bone defect model. Thus, further investigations are required to elucidate the underlying mechanisms and to develop efficient techniques for improved tissue regeneration. PMID:26825430

  4. Overexpression of Rac1 in leukemia patients and its role in leukemia cell migration and growth

    SciTech Connect

    Wang, Jiying; Rao, Qing; Wang, Min; Wei, Hui; Xing, Haiyan; Liu, Hang; Wang, Yanzhong; Tang, Kejing; Peng, Leiwen; Tian, Zheng; Wang, Jianxiang

    2009-09-04

    Rac1 belongs to the Rho family that act as critical mediators of signaling pathways controlling cell migration and proliferation and contributes to the interactions of hematopoietic stem cells with their microenvironment. Alteration of Rac1 might result in unbalanced interactions and ultimately lead to leukemogenesis. In this study, we analyze the expression of Rac1 protein in leukemia patients and determine its role in the abnormal behaviours of leukemic cells. Rac1 protein is overexpressed in primary acute myeloid leukemia cells as compared to normal bone marrow mononuclear cells. siRNA-mediated silencing of Rac1 in leukemia cell lines induced inhibition of cell migration, proliferation, and colony formation. Additionally, blocking Rac1 activity by an inhibitor of Rac1-GTPase, NSC23766, suppressed cell migration and growth. We conclude that overexpression of Rac1 contributes to the accelerated migration and high proliferation potential of leukemia cells, which could be implicated in leukemia development and progression.

  5. Overexpression of Rac1 in leukemia patients and its role in leukemia cell migration and growth.

    PubMed

    Wang, Jiying; Rao, Qing; Wang, Min; Wei, Hui; Xing, Haiyan; Liu, Hang; Wang, Yanzhong; Tang, Kejing; Peng, Leiwen; Tian, Zheng; Wang, Jianxiang

    2009-09-01

    Rac1 belongs to the Rho family that act as critical mediators of signaling pathways controlling cell migration and proliferation and contributes to the interactions of hematopoietic stem cells with their microenvironment. Alteration of Rac1 might result in unbalanced interactions and ultimately lead to leukemogenesis. In this study, we analyze the expression of Rac1 protein in leukemia patients and determine its role in the abnormal behaviours of leukemic cells. Rac1 protein is overexpressed in primary acute myeloid leukemia cells as compared to normal bone marrow mononuclear cells. siRNA-mediated silencing of Rac1 in leukemia cell lines induced inhibition of cell migration, proliferation, and colony formation. Additionally, blocking Rac1 activity by an inhibitor of Rac1-GTPase, NSC23766, suppressed cell migration and growth. We conclude that overexpression of Rac1 contributes to the accelerated migration and high proliferation potential of leukemia cells, which could be implicated in leukemia development and progression.

  6. Stem cells and transplant arteriosclerosis.

    PubMed

    Xu, Qingbo

    2008-05-01

    Stem cells can differentiate into a variety of cells to replace dead cells or to repair damaged tissues. Recent evidence indicates that stem cells are involved in the pathogenesis of transplant arteriosclerosis, an alloimmune initiated vascular stenosis that often results in transplant organ failure. Although the pathogenesis of transplant arteriosclerosis is not yet fully understood, recent developments in stem cell research have suggested novel mechanisms of vascular remodeling in allografts. For example, stem cells derived from the recipient may repair damaged endothelial cells of arteries in transplant organs. Further evidence suggests that stem cells or endothelial progenitor cells may be released from both bone marrow and non-bone marrow tissues. Vascular stem cells appear to replenish cells that died in donor vessels. Concomitantly, stem/progenitor cells may also accumulate in the intima, where they differentiate into smooth muscle cells. However, several issues concerning the contribution of stem cells to the pathogenesis of transplant arteriosclerosis are controversial, eg, whether bone marrow-derived stem cells can differentiate into smooth muscle cells that form neointimal lesions of the vessel wall. This review summarizes recent research on the role of stem cells in transplant arteriosclerosis, discusses the mechanisms of stem cell homing and differentiation into mature endothelial and smooth muscle cells, and highlights the controversial issues in the field.

  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. Effects of Telomerase and Telomere Length on Epidermal Stem Cell Behavior

    NASA Astrophysics Data System (ADS)

    Flores, Ignacio; Cayuela, María L.; Blasco, María A.

    2005-08-01

    A key process in organ homeostasis is the mobilization of stem cells out of their niches. We show through analysis of mouse models that telomere length, as well as the catalytic component of telomerase, Tert, are critical determinants in the mobilization of epidermal stem cells. Telomere shortening inhibited mobilization of stem cells out of their niche, impaired hair growth, and resulted in suppression of stem cell proliferative capacity in vitro. In contrast, Tert overexpression in the absence of changes in telomere length promoted stem cell mobilization, hair growth, and stem cell proliferation in vitro. The effects of telomeres and telomerase on stem cell biology anticipate their role in cancer and aging.

  9. Stem Cells in Mammalian Gonads.

    PubMed

    Wu, Ji; Ding, Xinbao; Wang, Jian

    2016-01-01

    Stem cells have great value in clinical application because of their ability to self-renew and their potential to differentiate into many different cell types. Mammalian gonads, including testes for males and ovaries for females, are composed of germline and somatic cells. In male mammals, spermatogonial stem cells maintain spermatogenesis which occurs continuously in adult testis. Likewise, a growing body of evidence demonstrated that female germline stem cells could be found in mammalian ovaries. Meanwhile, prior studies have shown that somatic stem cells exist in both testes and ovaries. In this chapter, we focus on mammalian gonad stem cells and discuss their characteristics as well as differentiation potentials.

  10. Characterization of amniotic stem cells.

    PubMed

    Koike, Chika; Zhou, Kaixuan; Takeda, Yuji; Fathy, Moustafa; Okabe, Motonori; Yoshida, Toshiko; Nakamura, Yukio; Kato, Yukio; Nikaido, Toshio

    2014-08-01

    The amnion membrane is developed from embryo-derived cells, and amniotic cells have been shown to exhibit multidifferentiation potential. These cells represent a desirable source for stem cells for a variety of reasons. However, to date very few molecular analyses of amnion-derived cells have been reported, and efficient markers for isolating the stem cells remain unclear. This paper assesses the characterization of amnion-derived cells as stem cells by examining stemness marker expressions for amnion-derived epithelial cells and mesenchymal cells by flow cytometry, immunocytochemistry, and quantitative PCR. Flow cytometry revealed that amnion epithelial cells expressed CD133, CD 271, and TRA-1-60, whereas mecenchymal cells expressed CD44, CD73, CD90, and CD105. Immunohistochemistry showed that both cells expressed the stemness markers Oct3/4, Sox2, Klf4, and SSEA4. Stemness genes' expression in amnion epithelial cells, mesenchymal cells, fibroblast, bone marrow-derived mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs) was compared by quantitative reverse-transcription polymerase chain reaction (RT-PCR). Amnion-derived epithelial cells and mesenchymal cells expressed Oct3/4, Nanog, and Klf4 more than bone marrow-derived MSCs. The sorted TRA1-60-positive cells expressed Oct3/4, Nanog, and Klf4 more than unsorted cells or TRA1-60-negative cells. TRA1-60 can be a marker for isolating amnion epithelial stem cells.

  11. Materials as stem cell regulators

    NASA Astrophysics Data System (ADS)

    Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

    2014-06-01

    The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine.

  12. Materials as stem cell regulators

    PubMed Central

    Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

    2014-01-01

    The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine. PMID:24845994

  13. A nucleolar mechanism controlling cell proliferation in stem cells and cancer cells

    PubMed Central

    Tsai, Robert Y.L.; McKay, Ronald D.G.

    2002-01-01

    The unique property of stem cells to self-renew suggests specific mechanisms that regulate their cell-cycle progression. In the present study, we identify a novel protein, nucleostemin, found in the nucleoli of CNS stem cells, embryonic stem cells, and several cancer cell lines and preferentially expressed by other stem cell-enriched populations. It contains an N-terminal basic domain and two GTP-binding motifs. When stem cells differentiate, nucleostemin expression decreases rapidly prior to cell-cycle exit both in vitro and in vivo. Depletion or overexpression of nucleostemin reduces cell proliferation in CNS stem cells and transformed cells. Mutation analysis indicates that excessive nucleostemin, particularly mutants that lack the GTP-regulatory domain, prevents cells from entering mitosis and causes apoptosis in a p53-dependent manner. The N-terminal basic domain specifies nucleolar localization, the p53 interaction, and is required for the cell death caused by overexpression. This work describes a novel nucleolar mechanism that controls the cell-cycle progression in CNS stem cells and cancer cells. PMID:12464630

  14. Atg3 Overexpression Enhances Bortezomib-Induced Cell Death in SKM-1 Cell

    PubMed Central

    Wang, Qian; Zhang, Jing; Zhu, Chen; Zhang, Lu; Xu, Xiaoping

    2016-01-01

    Background Myelodysplastic syndrome (MDS) is a group of heterogeneous hematopoietic stem cell malignancies with a high risk of transformation into acute myeloid leukemia (AML). Clonal evolutions are significantly associated with transformation to AML. According to a gene expression microarray, atg3 is downregulated in MDS patients progressing to leukemia, but less is known about the function of Atg3 in the survival and death of MSD/AML cells. Moreover, the role of autophagy as a result of bortezomib treatment is controversial. The current study was designed to investigate the function of Atg3 in SKM-1 cells and to study the effect of Atg3 on cell viability and cell death following bortezomib treatment. Methods Four leukemia cell lines (SKM-1, THP-1, NB4 and K562) and two healthy patients’ bone marrow cells were analyzed for Atg3 expression via qRT-PCR and Western blotting analysis. The role of Atg3 in SKM-1 cell survival and cell death was analyzed by CCK-8 assay, trypan blue exclusion assay, DAPI staining and Annexin V/PI dual staining with or without bortezomib treatment. Western blotting analysis was used to detect proteins in autophagic and caspase signaling pathways. Electron microscopy was used to observe ultrastructural changes after Atg3 overexpression. Results Downregulation of Atg3 expression was detected in four leukemia cell lines compared with healthy bone marrow cells. Atg3 mRNA was significantly decreased in MDS patients’ bone marrow cells. Overexpression of Atg3 in SKM-1 cells resulted in AKT-mTOR-dependent autophagy, a significant reduction in cell proliferation and increased cell death, which could be overcome by the autophagy inhibitor 3-MA. SKM-1 cells overexpressing Atg3 were hypersensitive to bortezomib treatment at different concentrations via autophagic cell death and enhanced sensitivity to apoptosis in the SKM-1 cell line. Following treatment with 3-MA, the sensitivity of Atg3-overexpressing cells to bortezomib treatment was reduced

  15. Cell therapy using induced pluripotent stem cells or somatic stem cells: this is the question.

    PubMed

    Somoza, Rodrigo A; Rubio, Francisco J

    2012-05-01

    A lot of effort has been developed to bypass the use of embryonic stem cells (ES) in human therapies, because of several concerns and ethical issues. Some unsolved problems of using stem cells for human therapies, excluding the human embryonic origin, are: how to regulate cell plasticity and proliferation, immunological compatibility, potential adverse side-effects when stem cells are systemically administrated, and the in vivo signals to rule out a specific cell fate after transplantation. Currently, it is known that almost all tissues of an adult organism have somatic stem cells (SSC). Whereas ES are primary involved in the genesis of new tissues and organs, SSC are involved in regeneration processes, immuno-regulatory and homeostasis mechanisms. Although the differentiating potential of ES is higher than SSC, several studies suggest that some types of SSC, such as mesenchymal stem cells (MSC), can be induced epigenetically to differentiate into tissue-specific cells of different lineages. This unexpected pluripotency and the variety of sources that they come from, can make MSC-like cells suitable for the treatment of diverse pathologies and injuries. New hopes for cell therapy came from somatic/mature cells and the discovery that could be reprogrammed to a pluripotent stage similar to ES, thus generating induced pluripotent stem cells (iPS). For this, it is necessary to overexpress four main reprogramming factors, Sox2, Oct4, Klf4 and c-Myc. The aim of this review is to analyze the potential and requirements of cellular based tools in human therapy strategies, focusing on the advantage of using MSC over iPS.

  16. Melanocytes, melanocyte stem cells, and melanoma stem cells.

    PubMed

    Lang, Deborah; Mascarenhas, Joseph B; Shea, Christopher R

    2013-01-01

    Melanocyte stem cells differ greatly from melanoma stem cells; the former provide pigmented cells during normal tissue homeostasis and repair, and the latter play an active role in a lethal form of cancer. These 2 cell types share several features and can be studied by similar methods. Aspects held in common by both melanocyte stem cells and melanoma stem cells include their expression of shared biochemical markers, a system of similar molecular signals necessary for their maintenance, and a requirement for an ideal niche microenvironment for providing these factors. This review provides a perspective of both these cell types and discusses potential models of stem cell growth and propagation. Recent findings provide a strong foundation for the development of new therapeutics directed at isolating and manipulating melanocyte stem cells for tissue engineering or at targeting and eradicating melanoma specifically, while sparing nontumor cells.

  17. Dental mesenchymal stem cells.

    PubMed

    Sharpe, Paul T

    2016-07-01

    Mammalian teeth harbour mesenchymal stem cells (MSCs), which contribute to tooth growth and repair. These dental MSCs possess many in vitro features of bone marrow-derived MSCs, including clonogenicity, expression of certain markers, and following stimulation, differentiation into cells that have the characteristics of osteoblasts, chondrocytes and adipocytes. Teeth and their support tissues provide not only an easily accessible source of MSCs but also a tractable model system to study their function and properties in vivo In addition, the accessibility of teeth together with their clinical relevance provides a valuable opportunity to test stem cell-based treatments for dental disorders. This Review outlines some recent discoveries in dental MSC function and behaviour and discusses how these and other advances are paving the way for the development of new biologically based dental therapies. PMID:27381225

  18. [Perinatal sources of stem cells].

    PubMed

    Piskorska-Jasiulewicz, Magdalena Maria; Witkowska-Zimny, Małgorzata

    2015-03-08

    Recently, stem cell biology has become an interesting topic. Several varieties of human stem cells have been isolated and identified in vivo and in vitro. Successful application of hematopoietic stem cells in hematology has led to the search for other sources of stem cells and expanding the scale of their application. Perinatal stem cells are a versatile cell population, and they are interesting for both scientific and practical objectives. Stem cells from perinatal tissue may be particularly useful in the clinic for autologous transplantation for fetuses and newborns, and after banking in later stages of life, as well as for in utero transplantation in the case of genetic disorders. In this review paper we focus on the extraction and therapeutic potential of stem cells derived from perinatal tissues such as the placenta, the amnion, amniotic fluid, umbilical cord blood and Wharton's jelly.

  19. Stem cell aging

    PubMed Central

    Muller-Sieburg, Christa; Sieburg, Hans B.

    2009-01-01

    The question whether stem cells age remains an enigma. Traditionally, aging was thought to change the properties of hematopoietic stem cells (HSC). We discuss here a new model of stem cell aging that challenges this view. It is now well-established that the HSC compartment is heterogeneous, consisting of epigenetically fixed subpopulations of HSC that differ in self-renewal and differentiation capacity. New data show that the representation of these HSC subsets changes during aging. HSC that generate lymphocyte-rich progeny are depleted, while myeloid-biased HSC are enriched in the aged HSC compartment. Myeloid-biased HSC, even when isolated from young donors, have most of the characteristics that had been attributed to aged HSC. Thus, the distinct behavior of the HSC isolated from aged hosts is due to the accumulation of myeloid-biased HSC. By extension this means that the properties of individual HSC are not substantially changed during the lifespan of the organism and that aged hosts do not contain many aged HSC. Myeloid-biased HSC give rise to mature cells slowly but contribute for a long time to peripheral hematopoiesis. We propose that such slow, “lazy” HSC are less likely to be transformed and therefore may safely sustain hematopoiesis for a long time. PMID:19066464

  20. Statins and stem cell modulation.

    PubMed

    Xu, Hui; Yang, Yue-Jin; Yang, Tao; Qian, Hai-Yan

    2013-01-01

    Stem cell-based therapy is a promising option for the treatment of ischemic heart diseases. As to a successful stem cell-based therapy, one of the most important issues is that the stable engraftment and survival of implanted stem cells in cardiac microenvironment. There are evidences suggest that pharmacological treatment devoted to regulate stem cell function might represent a potential new therapeutic strategy and are drawing nearer to becoming a part of treatment in clinical settings. Statins could exert cholesterol-independent or pleiotropic effects to cardiovascular system. Recent studies have shown that statins could modulate the biological characteristics and function of various stem cells, thus could be an effective method to facilitate stem cell therapy. This review will focus on statins and their modulation effects on various stem cells.

  1. Ovarian cancer stem cells enrichment.

    PubMed

    Yang, Lijuan; Lai, Dongmei

    2013-01-01

    The concept of cancer stem cells (CSCs) provides a new paradigm for understanding cancer biology. Cancer stem cells are defined as a minority of cancer cells with stem cell properties responsible for maintenance and growth of tumors. The targeting of CSCs is a potential therapeutic strategy to combat ovarian cancer. Ovarian epithelial cancer cells cultured in serum-free medium can form sphere cells. These sphere cells may be enriched for cancer stem cells (CSCs). The isolation of sphere cells from solid tumors is an important technique in studying cancer cell biology. Here we describe the isolation of sphere cells from primary ovarian cancer tissue, ascites fluid, and the cancer cell line SKOV3 with stem cell selection medium. PMID:23913228

  2. Breast Cancer Stem Cells

    PubMed Central

    Velasco-Velázquez, Marco A.; Homsi, Nora; De La Fuente, Marisol; Pestell, Richard G.

    2012-01-01

    Breast cancer stem cells (BCSCs) constitute a subpopulation of tumor cells that express stem cell-associated markers and have a high capacity for tumor generation in vivo. Identification of BCSCs from tumor samples or breast cancer cell lines has been based mainly on CD44+/CD24−/low or ALDH+ phenotypes. BCSCs isolation has allowed the analysis of the molecular mechanisms involved in their origin, self-renewal, differentiation into tumor cells, resistance to radiation therapy and chemotherapy, and invasiveness and metastatic ability. Molecular genetic analysis using knockout animals and inducible transgenics have identified NF-κB, c-Jun, p21CIP1, and Forkhead-like-protein Dach1 in BCSC expansion and fate. Clinical analyses of BCSCs in breast tumors have found a correlation between the proportion of BCSCs and poor prognosis. Therefore, new therapies that specifically target BCSCs are an urgent need. We summarize recent evidence that partially explain the biological characteristics of BCSCs. PMID:22249027

  3. Macrophages overexpressing Aire induce CD4+Foxp3+ T cells.

    PubMed

    Sun, Jitong; Fu, Haiying; Wu, Jing; Zhu, Wufei; Li, Yi; Yang, Wei

    2013-01-01

    Aire plays an important role in central immune tolerance by regulating the transcription of thousands of genes. However, the role of Aire in the peripheral immune system is poorly understood. Regulatory T (Treg) cells are considered essential for the maintenance of peripheral tolerance, but the effect of Aire on Treg cells in the peripheral immune system is currently unknown. In this study, we investigated the effects of macrophages overexpressing Aire on CD4+Foxp3+ Treg cells by co-culturing Aire-overexpressing RAW264.7 cells or their supernatant with splenocytes. The results show that macrophages overexpressing Aire enhanced the expression of Foxp3 mRNA and induced different subsets of Treg cells in splenocytes through cell-cell contact or a co-culture supernatants. TGF-β is a key molecule in the increases of CD4+CD45RA+Foxp3hi T cell and activating Treg (aTreg) levels observed following cell‑supernatant co-culturing. Subsets of Treg cells were induced by Aire-overexpressing macrophages, and the manipulation of Treg cells by the targeting of Aire may provide a method for the treatment of inflammatory or autoimmune diseases.

  4. Pancreatic cancer stem cells

    PubMed Central

    Zhu, Ya-Yun; Yuan, Zhou

    2015-01-01

    Studies are emerging in support of the cancer stem cells (CSCs) theory which considers that a tiny subset of cancer cells is exclusively responsible for the initiation and malignant behavior of a cancer. This cell population, also termed CSCs, possesses the capacity both to self-renew, producing progeny that have the identical tumorigenic potential, and to differentiate into the bulk of cancer cells, helping serve the formation of the tumor entities, which, altogether, build the hierarchically organized structure of a cancer. In this review, we try to articulate the complicated signaling pathways regulating the retention of the characteristics of pancreatic CSCs, and in the wake of which, we seek to offer insights into the CSCs-relevant targeted therapeutics which are, in the meantime, confronted with bigger challenges than ever. PMID:26045976

  5. Stem cells and neurodegenerative diseases.

    PubMed

    Hou, LingLing; Hong, Tao

    2008-04-01

    Neurodegenerative diseases are characterized by the neurodegenerative changes or apoptosis of neurons involved in networks, which are important to specific physiological functions. With the development of old-aging society, the incidence of neurodegenerative diseases is on the increase. However, it is difficult to diagnose for most of neurodegenerative diseases. At present, there are too few effective therapies. Advances in stem cell biology have raised the hope and possibility for the therapy of neurodegenerative diseases. Recently, stem cells have been widely attempted to treat neurodegenerative diseases of animal model. Here we review the progress and prospects of various stem cells, including embryonic stem cells, mesenchymal stem cell and neural stem cells and so on, for the treatments of neurodegenerative diseases, such as Parkinson's disease, Alzheimer's disease, Huntington' disease and Amyotrophic lateral sclerosis/Lou Gehrig's disease.

  6. Skeletal stem cells

    PubMed Central

    Bianco, Paolo; Robey, Pamela G.

    2015-01-01

    Skeletal stem cells (SSCs) reside in the postnatal bone marrow and give rise to cartilage, bone, hematopoiesis-supportive stroma and marrow adipocytes in defined in vivo assays. These lineages emerge in a specific sequence during embryonic development and post natal growth, and together comprise a continuous anatomical system, the bone-bone marrow organ. SSCs conjoin skeletal and hematopoietic physiology, and are a tool for understanding and ameliorating skeletal and hematopoietic disorders. Here and in the accompanying poster, we concisely discuss the biology of SSCs in the context of the development and postnatal physiology of skeletal lineages, to which their use in medicine must remain anchored. PMID:25758217

  7. Mechanotransduction: Tuning Stem Cells Fate

    PubMed Central

    D'Angelo, Francesco; Tiribuzi, Roberto; Armentano, Ilaria; Kenny, Josè Maria; Martino, Sabata; Orlacchio, Aldo

    2011-01-01

    It is a general concern that the success of regenerative medicine-based applications is based on the ability to recapitulate the molecular events that allow stem cells to repair the damaged tissue/organ. To this end biomaterials are designed to display properties that, in a precise and physiological-like fashion, could drive stem cell fate both in vitro and in vivo. The rationale is that stem cells are highly sensitive to forces and that they may convert mechanical stimuli into a chemical response. In this review, we describe novelties on stem cells and biomaterials interactions with more focus on the implication of the mechanical stimulation named mechanotransduction. PMID:24956164

  8. Stem Cells, Redox Signaling, and Stem Cell Aging

    PubMed Central

    Liang, Raymond

    2014-01-01

    Abstract Significance: Functional stem cell decline has been postulated to result in loss of maintenance of tissue homeostasis leading to organismal decline and diseases of aging. Recent Advances: Recent findings implicate redox metabolism in the control of stem cell pool and stem cell aging. Although reactive oxygen species (ROS) are better known for their damaging properties to DNA, proteins and lipids, recent findings suggest that ROS may also be an integral physiological mediator of cellular signaling in primary cells. Critical Issues: Here we review recent published work on major signaling pathways and transcription factors that are regulated by ROS and mediate ROS regulation of stem cell fate. We will specifically focus on how alterations in this regulation may be implicated in disease and particularly in diseases of stem cell aging. In general, based on the work described here we propose a model in which ROS function as stem cell rheostat. Future Directions: Future work in elucidating how ROS control stem cell cycling, apoptotic machinery, and lineage determination should shed light on mechanisms whereby ROS may control stem cell aging. Antioxid. Redox Signal. 20, 1902–1916. PMID:24383555

  9. [Stem cells and cardiac regeneration].

    PubMed

    Perez Millan, Maria Ines; Lorenti, Alicia

    2006-01-01

    Stem cells are defined by virtue of their functional attributes: absence of tissue specific differentitated markers, capable of proliferation, able to self-maintain the population, able to produce a large number of differentiated, functional progeny, able to regenerate the tissue after injury. Cell therapy is an alternative for the treatment of several diseases, like cardiac diseases (cell cardiomyoplasty). A variety of stem cells could be used for cardiac repair: from cardiac and extracardiac sources. Each cell type has its own profile of advantages, limitations, and practicability issues in specific clinical settings. Differentiation of bone marrow stem cells to cardiomyocyte-like cells have been observed under different culture conditions. The presence of resident cardiac stem cell population capable of differentiation into cardiomyocyte or vascular lineage suggests that these cells could be used for cardiac tissue repair, and represent a great promise for clinical application. Stem cells mobilization by cytokines may also offer a strategy for cardiac regeneration. The use of stem cells (embryonic and adult) may hold the key to replacing cells lost in many devastating diseases. This potential benefit is a major focus for stem cell research.

  10. Involvement of Plant Stem Cells or Stem Cell-Like Cells in Dedifferentiation.

    PubMed

    Jiang, Fangwei; Feng, Zhenhua; Liu, Hailiang; Zhu, Jian

    2015-01-01

    Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells) are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation. PMID:26635851

  11. The new stem cell biology.

    PubMed Central

    Quesenberry, Peter J.; Colvin, Gerald A.; Lambert, Jean-Francois; Frimberger, Angela E.; Dooner, Mark S.; Mcauliffe, Christina I.; Miller, Caroline; Becker, Pamela; Badiavas, Evangelis; Falanga, Vincent J.; Elfenbein, Gerald; Lum, Lawrence G.

    2002-01-01

    Recent studies have indicated that bone marrow stem cells are capable of generating muscle, cardiac, hepatic, renal, and bone cells. Purified hematopoietic stem cells have generated cardiac and hepatic cells and reversed disease manifestations in these tissues. Hematopoietic stem cells also alter phenotype with cell cycle transit or circadian phase. During a cytokine stimulated cell cycle transit, reversible alterations of differentiation and engraftment occur. Primitive hematopoietic stem cells express a wide variety of adhesion and cytokine receptors and respond quickly with migration and podia extensions on exposure to cytokines. These data suggest an "Open Chromatin" model of stem cell regulation in which there is a fluctuating continuum in the stem cell/progenitor cell compartments, rather than a hierarchical relationship. These observations, along with progress in using low dose treatments and tolerization approaches, suggest many new therapeutic strategies involving stem cells and the creation of a new medical specialty; stemology. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:12053709

  12. Stem cells in pharmaceutical biotechnology.

    PubMed

    Zuba-Surma, Ewa K; Józkowicz, Alicja; Dulak, Józef

    2011-11-01

    Multiple populations of stem cells have been indicated to potentially participate in regeneration of injured organs. Especially, embryonic stem cells (ESC) and recently inducible pluripotent stem cells (iPS) receive a marked attention from scientists and clinicians for regenerative medicine because of their high proliferative and differentiation capacities. Despite that ESC and iPS cells are expected to give rise into multiple regenerative applications when their side effects are overcame during appropriate preparation procedures, in fact their most recent application of human ESC may, however, reside in their use as a tool in drug development and disease modeling. This review focuses on the applications of stem cells in pharmaceutical biotechnology. We discuss possible relevance of pluripotent cell stem populations in developing physiological models for any human tissue cell type useful for pharmacological, metabolic and toxicity evaluation necessary in the earliest steps of drug development. The present models applied for preclinical drug testing consist of primary cells or immortalized cell lines that show limitations in terms of accessibility or relevance to their in vivo counterparts. The availability of renewable human cells with functional similarities to their in vivo counterparts is the first landmark for a new generation of cell-based assays. We discuss the approaches for using stem cells as valuable physiological targets of drug activity which may increase the strength of target validation and efficacy potentially resulting in introducing new safer remedies into clinical trials and the marketplace. Moreover, we discuss the possible applications of stem cells for elucidating mechanisms of disease pathogenesis. The knowledge about the mechanisms governing the development and progression of multitude disorders which would come from the cellular models established based on stem cells, may give rise to new therapeutical strategies for such diseases. All

  13. Bioprinting for stem cell research

    PubMed Central

    Tasoglu, Savas; Demirci, Utkan

    2012-01-01

    Recently, there has been a growing interest to apply bioprinting techniques to stem cell research. Several bioprinting methods have been developed utilizing acoustics, piezoelectricity, and lasers to deposit living cells onto receiving substrates. Using these technologies, spatially defined gradients of immobilized proteins can be engineered to direct stem cell differentiation into multiple subpopulations of different lineages. Stem cells can also be patterned in a high-throughput manner onto flexible implementation patches for tissue regeneration or onto substrates with the goal of accessing encapsulated stem cell of interest for genomic analysis. Here, we review recent achievements with bioprinting technologies in stem cell research, and identify future challenges and potential applications including tissue engineering and regenerative medicine, wound healing, and genomics. PMID:23260439

  14. Stem cells for spine surgery.

    PubMed

    Schroeder, Joshua; Kueper, Janina; Leon, Kaplan; Liebergall, Meir

    2015-01-26

    In the past few years, stem cells have become the focus of research by regenerative medicine professionals and tissue engineers. Embryonic stem cells, although capable of differentiating into cell lineages of all three germ layers, are limited in their utilization due to ethical issues. In contrast, the autologous harvest and subsequent transplantation of adult stem cells from bone marrow, adipose tissue or blood have been experimentally utilized in the treatment of a wide variety of diseases ranging from myocardial infarction to Alzheimer's disease. The physiologic consequences of stem cell transplantation and its impact on functional recovery have been studied in countless animal models and select clinical trials. Unfortunately, the bench to bedside translation of this research has been slow. Nonetheless, stem cell therapy has received the attention of spinal surgeons due to its potential benefits in the treatment of neural damage, muscle trauma, disk degeneration and its potential contribution to bone fusion.

  15. The advantages of hair follicle pluripotent stem cells over embryonic stem cells and induced pluripotent stem cells for regenerative medicine.

    PubMed

    Amoh, Yasuyuki; Katsuoka, Kensei; Hoffman, Robert M

    2010-12-01

    Multipotent adult stem cells have many potential therapeutic applications. Our recent findings suggest that hair follicles are a promising source of easily accessible multipotent stem cells. Stem cells in the hair follicle area express the neural stem cell marker nestin, suggesting that hair-follicle stem cells and neural stem cells have common features. Nestin-expressing hair follicle stem cells can form neurons and other cell types, and thus adult hair follicle stem cells could have important therapeutic applications, particularly for neurologic diseases. Transplanted hair follicle stem cells promote the functional recovery of injured peripheral nerve and spinal cord. Recent findings suggest that direct transplantation of hair-follicle stem cells without culture can promote nerve repair, which makes them potentially clinically practical. Human hair follicle stem cells as well as mouse hair follicle stem cells promote nerve repair and can be applied to test the hypothesis that human hair follicle stem cells can provide a readily available source of neurologically therapeutic stem cells. The use of hair follicle stem cells for nerve regeneration overcomes critical problems of embryonic stem cells or induced pluripotent stem cells in that the hair follicle stem cells are multipotent, readily accessible, non-oncogenic, and are not associated with ethical issues.

  16. Stem cells, colorectal cancer and cancer stem cell markers correlations.

    PubMed

    Cherciu, Irina; Bărbălan, A; Pirici, D; Mărgăritescu, C; Săftoiu, A

    2014-01-01

    : The idea of stem cells as being progenitors of cancer was initially controversial, but later supported by research in the field of leukemia and solid tumors. Afterwards, it was established that genetic abnormalities can affect the stem and progenitor cells, leading to uncontrolled replication and deregulated differentiation. These alterations will cause the changeover to cancerous stem cells (CSC) having two main characteristics: tumor initiation and maintenance. This review will focus on the colorectal cancer stem cell (CR-CSCs) theory which provides a better understanding of different tumor processes: initiation, aggressive growth, recurrence, treatment resistance and metastasis. A search in PubMed/Medline was performed using the following keywords: colorectal cancer stem cells (CR-CSCs), colorectal neoplasms stem cells, colorectal cancer stem cell (CR-CSCs) markers, etc. Electronic searches were supplemented by hand searching reference lists, abstracts and proceedings from meetings. Isolation of CR-CSCs can be achieved by targeting and selecting subpopulation of tumor cells based on expression of one or multiple cell surface markers associated with cancer self-renewal, markers as: CD133, CD166, CD44, CD24, beta1 integrin-CD29, Lgr5, EpCAM (ESA), ALDH-1, Msi-1, DCAMLK1 or EphB receptors. The identification and localization of CR-CSCs through different markers will hopefully lead to a better stratification of prognosis and treatment response, as well as the development of new effective strategies for cancer management.

  17. FDA Warns About Stem Cell Claims

    MedlinePlus

    ... Home For Consumers Consumer Updates FDA Warns About Stem Cell Claims Share Tweet Linkedin Pin it More sharing ... blood-forming system. back to top Regulation of Stem Cells FDA regulates stem cells in the U.S. to ...

  18. LncRNAs in Stem Cells

    PubMed Central

    Hu, Shanshan; Shan, Ge

    2016-01-01

    Noncoding RNAs are critical regulatory factors in essentially all forms of life. Stem cells occupy a special position in cell biology and Biomedicine, and emerging results show that multiple ncRNAs play essential roles in stem cells. We discuss some of the known ncRNAs in stem cells such as embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells, adult stem cells, and cancer stem cells with a focus on long ncRNAs. Roles and functional mechanisms of these lncRNAs are summarized, and insights into current and future studies are presented. PMID:26880946

  19. Stem cells: review and update.

    PubMed

    Sylvester, Karl G; Longaker, Michael T

    2004-01-01

    Regenerative medicine and emerging biotechnologies stand to revolutionize the practice of medicine. Advancements in stem cell biology, including embryonic and postnatal somatic stem cells, have made the prospect of tissue regeneration a potential clinical reality. Short of reproductive cloning, these same technologies, properly used, could allow for the creation of replacement tissue for the deficient host. To provide a concise review for surgeons on the current science and biology of stem cells, we surveyed the scientific literature, MEDLINE, and relevant political headlines that illuminate the stem cell discussion; the issues are summarized in this review. Building on this conceptual framework, the related issues of clinical promise and the political debate enveloping this emerging technology are examined. A basic understanding of stem cell biology is paramount to stay informed of this emerging technology and the national debate.

  20. Nerve Allografts Supplemented with Schwann Cells Overexpressing GDNF

    PubMed Central

    Santosa, Katherine B.; Jesuraj, Nithya J.; Viader, Andreu; MacEwan, Matthew; Newton, Piyaraj; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

    2012-01-01

    Introduction We sought to determine if supplementation of acellular nerve allografts (ANAs) with Schwann Cells overexpressing GDNF (G-SCs) would enhance functional recovery following peripheral nerve injury. Methods SCs expanded in vitro were infected with a lentiviral vector to induce GDNF overexpression. Wild type-SCs (WT-SCs) and G-SCs were seeded into ANAs used to repair a 14mm nerve gap defect. Animals were harvested after 6 and 12 weeks for histomorphometric and muscle force analysis. Results At 6 weeks, histomorphometry revealed that ANAs supplemented with G-SCs promoted similar regeneration compared to the isograft at midgraft. However, G-SCs failed to promote regeneration into the distal stump. At 12 weeks, ANAs with G-SCs had lower maximum and specific force production compared to controls. Discussion The combined results suggest that consistent overexpression of GDNF by G-SCs trapped axons in the graft and prevented functional regeneration. PMID:23169341

  1. Stem Cells, Retinal Ganglion Cells, and Glaucoma

    PubMed Central

    Sluch, Valentin M.; Zack, Donald J.

    2015-01-01

    Retinal ganglion cells represent an essential neuronal cell type for vision. These cells receive inputs from light-sensing photoreceptors via retinal interneurons and then relay these signals to the brain for further processing. Retinal ganglion cell diseases that result in cell death, e.g. glaucoma, often lead to permanent damage since mammalian nerves do not regenerate. Stem cell differentiation can generate cells needed for replacement or can be used to generate cells capable of secreting protective factors to promote survival. In addition, stem cell-derived cells can be used in drug screening research. Here, we discuss the current state of stem cell research potential for interference in glaucoma and other optic nerve diseases with a focus on stem cell differentiation to retinal ganglion cells. PMID:24732765

  2. Gastrointestinal stem cell up-to-date.

    PubMed

    Pirvulet, V

    2015-01-01

    Cellular and tissue regeneration in the gastrointestinal tract depends on stem cells with properties of self-renewal, clonogenicity, and multipotency. Progress in stem cell research and the identification of potential gastric, intestinal, colonic stem cells new markers and the signaling pathways provide hope for the use of stem cells in regenerative medicine and treatments for disease. This review provides an overview of the different types of stem cells, focusing on tissue-restricted adult stem cells.

  3. Keratinocyte stem cells: a commentary.

    PubMed

    Potten, Christopher S; Booth, Catherine

    2002-10-01

    For many years it has been widely accepted that stem cells play a crucial role in adult tissue maintenance. The concept that the renewing tissues of the body contain a small subcompartment of self-maintaining stem cells, upon which the entire tissue is dependent, is also now accepted as applicable to all renewing tissues. Gene therapy and tissue engineering are driving considerable interest in the clinical application of such hierarchically organized cellular compartments. Recent initial observations have provided a tantalizing insight into the large pluripotency of these cells. Indeed, scientists are now beginning to talk about the possible totipotency of some adult tissue stem cells. Such work is currently phenomenologic, but analysis of data derived from genomics and proteomics, identifying the crucial control signals involved, will soon provide a further impetus to stem cell biology with far reaching applications. The epidermis with its relatively simple structure, ease of accessibility, and the ability to grow its cells in vitro is one obvious target tissue for testing stem cell manipulation theories. It is crucial, however, that the normal keratinocyte stem cell is thoroughly characterized prior to attempting to manipulate its pluripotency. This commentary assesses the data generated to date and critically discusses the conclusions that have been drawn. Our current level of understanding, or lack of understanding, of the keratinocyte stem cell is reviewed.

  4. A Comparison of Culture Characteristics between Human Amniotic Mesenchymal Stem Cells and Dental Stem Cells.

    PubMed

    Yusoff, Nurul Hidayat; Alshehadat, Saaid Ayesh; Azlina, Ahmad; Kannan, Thirumulu Ponnuraj; Hamid, Suzina Sheikh Abdul

    2015-04-01

    In the past decade, the field of stem cell biology is of major interest among researchers due to its broad therapeutic potential. Stem cells are a class of undifferentiated cells that are able to differentiate into specialised cell types. Stem cells can be classified into two main types: adult stem cells (adult tissues) and embryonic stem cells (embryos formed during the blastocyst phase of embryological development). This review will discuss two types of adult mesenchymal stem cells, dental stem cells and amniotic stem cells, with respect to their differentiation lineages, passage numbers and animal model studies. Amniotic stem cells have a greater number of differentiation lineages than dental stem cells. On the contrary, dental stem cells showed the highest number of passages compared to amniotic stem cells. For tissue regeneration based on animal studies, amniotic stem cells showed the shortest time to regenerate in comparison with dental stem cells.

  5. Cell rheology: Stressed-out stem cells

    NASA Astrophysics Data System (ADS)

    Holle, Andrew W.; Engler, Adam J.

    2010-01-01

    Experiments have shown that the physical characteristics of the matrix surrounding a stem cell can affect its behaviour. This picture gets further complicated by studies of stem cells and their differentiated counterparts that show that the cells' own softness also has a clear role in how they respond to stress.

  6. Yap tunes airway epithelial size and architecture by regulating the identity, maintenance, and self-renewal of stem cells.

    PubMed

    Zhao, Rui; Fallon, Timothy R; Saladi, Srinivas Vinod; Pardo-Saganta, Ana; Villoria, Jorge; Mou, Hongmei; Vinarsky, Vladimir; Gonzalez-Celeiro, Meryem; Nunna, Naveen; Hariri, Lida P; Camargo, Fernando; Ellisen, Leif W; Rajagopal, Jayaraj

    2014-07-28

    Our understanding of how stem cells are regulated to maintain appropriate tissue size and architecture is incomplete. We show that Yap (Yes-associated protein 1) is required for the actual maintenance of an adult mammalian stem cell. Without Yap, adult airway basal stem cells are lost through their unrestrained differentiation, resulting in the simplification of a pseudostratified epithelium into a columnar one. Conversely, Yap overexpression increases stem cell self-renewal and blocks terminal differentiation, resulting in epithelial hyperplasia and stratification. Yap overexpression in differentiated secretory cells causes them to partially reprogram and adopt a stem cell-like identity. In contrast, Yap knockdown prevents the dedifferentiation of secretory cells into stem cells. We then show that Yap functionally interacts with p63, the cardinal transcription factor associated with myriad epithelial basal stem cells. In aggregate, we show that Yap regulates all of the cardinal behaviors of airway epithelial stem cells and determines epithelial architecture.

  7. Bone regeneration and stem cells

    PubMed Central

    Arvidson, K; Abdallah, B M; Applegate, L A; Baldini, N; Cenni, E; Gomez-Barrena, E; Granchi, D; Kassem, M; Konttinen, Y T; Mustafa, K; Pioletti, D P; Sillat, T; Finne-Wistrand, A

    2011-01-01

    Abstract This invited review covers research areas of central importance for orthopaedic and maxillofacial bone tissue repair, including normal fracture healing and healing problems, biomaterial scaffolds for tissue engineering, mesenchymal and foetal stem cells, effects of sex steroids on mesenchymal stem cells, use of platelet-rich plasma for tissue repair, osteogenesis and its molecular markers. A variety of cells in addition to stem cells, as well as advances in materials science to meet specific requirements for bone and soft tissue regeneration by addition of bioactive molecules, are discussed. PMID:21129153

  8. Stem cell therapy without the cells

    PubMed Central

    Maguire, Greg

    2013-01-01

    As an example of the burgeoning importance of stem cell therapy, this past month the California Institute for Regenerative Medicine (CIRM) has approved $70 million to create a new network of stem cell clinical trial centers. Much work in the last decade has been devoted to developing the use of autologous and allogeneic adult stem cell transplants to treat a number of conditions, including heart attack, dementia, wounds, and immune system-related diseases. The standard model teaches us that adult stem cells exists throughout most of the body and provide a means to regenerate and repair most tissues through replication and differentiation. Although we have often witnessed the medical cart placed in front of the scientific horse in the development of stem cell therapies outside of academic circles, great strides have been made, such as the use of purified stem cells1 instead of whole bone marrow transplants in cancer patients, where physicians avoid re-injecting the patients with their own cancer cells.2 We most often think of stem cell therapy acting to regenerate tissue through replication and then differentiation, but recent studies point to the dramatic effects adult stem cells exert in the repair of various tissues through the release of paracrine and autocrine substances, and not simply through differentiation. Indeed, up to 80% of the therapeutic effect of adult stem cells has been shown to be through paracrine mediated actions.3 That is, the collected types of molecules released by the stem cells, called the secretome, or stem cell released molecules (SRM), number in the 100s, including proteins, microRNA, growth factors, antioxidants, proteasomes, and exosomes, and target a multitude of biological pathways through paracrine actions. The composition of the different molecule types in SRM is state dependent, and varies with cell type and conditions such as age and environment. PMID:24567776

  9. Advances in culture and manipulation of human pluripotent stem cells.

    PubMed

    Qian, X; Villa-Diaz, L G; Krebsbach, P H

    2013-11-01

    Recent advances in the understanding of pluripotent stem cell biology and emerging technologies to reprogram somatic cells to a stem cell-like state are helping bring stem cell therapies for a range of human disorders closer to clinical reality. Human pluripotent stem cells (hPSCs) have become a promising resource for regenerative medicine and research into early development because these cells are able to self-renew indefinitely and are capable of differentiation into specialized cell types of all 3 germ layers and trophoectoderm. Human PSCs include embryonic stem cells (hESCs) derived from the inner cell mass of blastocyst-stage embryos and induced pluripotent stem cells (hiPSCs) generated via the reprogramming of somatic cells by the overexpression of key transcription factors. The application of hiPSCs and the finding that somatic cells can be directly reprogrammed into different cell types will likely have a significant impact on regenerative medicine. However, a major limitation for successful therapeutic application of hPSCs and their derivatives is the potential xenogeneic contamination and instability of current culture conditions. This review summarizes recent advances in hPSC culture and methods to induce controlled lineage differentiation through regulation of cell-signaling pathways and manipulation of gene expression as well as new trends in direct reprogramming of somatic cells.

  10. Microbioreactors for Stem Cell Research

    NASA Astrophysics Data System (ADS)

    Freytes, Donald O.; Vunjak-Novakovic, Gordana

    During tissue development and regeneration, stem cells respond to the entire milieu of their environment, through dynamic interactions with the surrounding cells, extracellular matrix, and cascades of molecular and physical regulatory factors. A new generation of culture systems is emerging to offer some of the biological fidelity of a whole organism within highly controllable in vitro settings and provide the cultured cells with the combinations of factors they normally encounter in vivo. There is a growing notion that such "biomimetic" systems are essential for unlocking the full potential of stem cells - for tissue regeneration as well as biological research. In this chapter, we discuss the biological principles for designing biologically inspired culture systems for stem cell research and focus on the control of stem cell microenvironment through surface patterning, microfluidics, and electrical stimulation.

  11. Stem cells and combinatorial science.

    PubMed

    Fang, Yue Qin; Wong, Wan Qing; Yap, Yan Wen; Orner, Brendan P

    2007-09-01

    Stem cell-based technologies have the potential to help cure a number of cell degenerative diseases. Combinatorial and high throughput screening techniques could provide tools to control and manipulate the self-renewal and differentiation of stem cells. This review chronicles historic and recent progress in the stem cell field involving both pluripotent and multipotent cells, and it highlights relevant cellular signal transduction pathways. This review further describes screens using libraries of soluble, small-molecule ligands, and arrays of molecules immobilized onto surfaces while proposing future trends in similar studies. It is hoped that by reviewing both the stem cell and the relevant high throughput screening literature, this paper can act as a resource to the combinatorial science community.

  12. Overexpression of ankyrin1 promotes pancreatic cancer cell growth

    PubMed Central

    Omura, Noriyuki; Mizuma, Masamichi; MacGregor, Anne; Hong, Seung-Mo; Ayars, Michael; Almario, Jose Alejandro; Borges, Michael; Kanda, Mitsuro; Li, Ang; Vincent, Audrey; Maitra, Anirban; Goggins, Michael

    2016-01-01

    The methylation status of a promoter influences gene expression and aberrant methylation during tumor development has important functional consequences for pancreatic and other cancers. Using methylated CpG island amplification and promoter microarrays, we identified ANK1 as hypomethylated in pancreatic cancers. Expression analysis determined ANK1 as commonly overexpressed in pancreatic cancers relative to normal pancreas. ANK1 was co-expressed with miR-486 in pancreatic cancer cells. Stable knockdown of ANK1 in the pancreatic cancer cell line AsPC1 led to changes in cell morphology, and decreases in colony formation. Stable knockdown of ANK1 also marked reduced the growth of tumors in athymic nude mice. Among patients undergoing pancreaticoduodenectomy, those with pancreatic cancers expressing ANK1 had a poorer prognosis than those without ANK1 expression. These findings indicate a role for ANK1 overexpression in mediating pancreatic cancer tumorigenicity. PMID:27144336

  13. The embryonic stem cell test.

    PubMed

    Schulpen, Sjors H W; Piersma, Aldert H

    2013-01-01

    The embryonic stem cell test is an animal-free alternative test method for developmental toxicity. Mouse embryonic stem cells are cultured in a hanging drop method to form embryoid bodies. These embryoid bodies, when plated on tissue culture dishes, differentiate to form contracting myocardial cell foci within 10 days. Inhibition of cardiomyocyte differentiation by test compounds serves as the end point of the assay, as monitored by counting contracting muscle foci under the microscope.

  14. Harvesting dental stem cells - Overview

    PubMed Central

    Sunil, P. M.; Manikandan, Ramanathan; Muthumurugan; Yoithapprabhunath, Thukanayakanpalayam Ragunathan; Sivakumar, Muniapillai

    2015-01-01

    Dental stem cells have recently become one of the widely researched areas in dentistry. Ever since the identification of stem cells from various dental tissues like deciduous teeth, dental papilla, periodontal ligament and third molars, storing them for future use for various clinical applications was being explored. Dental stem cells were harvested and isolated using various techniques by different investigators and laboratories. This article explains the technical aspects of preparing the patient, atraumatic and aseptic removal of the tooth and its safe transportation and preservation for future expansion. PMID:26538883

  15. Stem cells, dot-com.

    PubMed

    Liang, Bryan A; Mackey, Tim K

    2012-09-12

    Direct-to-consumer (DTC) advertising of suspect goods and services has burgeoned because of the Internet. Despite very limited approval for use, DTC stem cell-marketed "treatments" have emerged for an array of conditions, creating global public health and safety risks. However, it remains unclear whether such use of stem cells is subject to drugs or biologics regulations. To address this gap, regulatory agencies should be given clear authority, and the international community should create a framework for appropriate stem cell use. In addition, consumer protection laws should be used to scrutinize providers.

  16. Advances in stem cell therapy.

    PubMed

    Pérez López, Silvia; Otero Hernández, Jesús

    2012-01-01

    Since the beginning of stem cell biology, considerable effort has been focused in the translation of scientific insights into new therapies. Cell-based assays represent a new strategy for organ and tissue repair in several pathologies. Moreover, alternative treatment strategies are urgently needed due to donor organ shortage that costs many lives every year and results in lifelong immunosuppression. At the moment, only the use of hematopoietic stem cells is considered as the standard for the treatment of malignant and genetic bone marrow disorders, being all other stem cell applications highly experimental. The present chapter tries to summarize some ongoing approaches of stem cell regenerative medicine and also introduces recent findings from published studies and trials conducted in various tissues such as skeletal muscle, liver and lung.

  17. Diabetes and stem cell function.

    PubMed

    Fujimaki, Shin; Wakabayashi, Tamami; Takemasa, Tohru; Asashima, Makoto; Kuwabara, Tomoko

    2015-01-01

    Diabetes mellitus is one of the most common serious metabolic diseases that results in hyperglycemia due to defects of insulin secretion or insulin action or both. The present review focuses on the alterations to the diabetic neuronal tissues and skeletal muscle, including stem cells in both tissues, and the preventive effects of physical activity on diabetes. Diabetes is associated with various nervous disorders, such as cognitive deficits, depression, and Alzheimer's disease, and that may be caused by neural stem cell dysfunction. Additionally, diabetes induces skeletal muscle atrophy, the impairment of energy metabolism, and muscle weakness. Similar to neural stem cells, the proliferation and differentiation are attenuated in skeletal muscle stem cells, termed satellite cells. However, physical activity is very useful for preventing the diabetic alteration to the neuronal tissues and skeletal muscle. Physical activity improves neurogenic capacity of neural stem cells and the proliferative and differentiative abilities of satellite cells. The present review proposes physical activity as a useful measure for the patients in diabetes to improve the physiological functions and to maintain their quality of life. It further discusses the use of stem cell-based approaches in the context of diabetes treatment.

  18. RACK-1 overexpression protects against goniothalamin-induced cell death

    PubMed Central

    Inayat-Hussain, S.H.; Wong, L.T.; Chan, K.M.; Rajab, N.F.; Din, L.B.; Harun, R.; Kizilors, A.; Saxena, N.; Mourtada-Maarabouni, M.; Farzaneh, F.; Williams, G.T.

    2009-01-01

    Goniothalamin, a styryllactone, has been shown to induce cytotoxicity via apoptosis in several tumor cell lines. In this study, we have examined the potential role of several genes, which were stably transfected into T-cell lines and which regulate apoptosis in different ways, on goniothalamin-induced cell death. Overexpression of full-length receptor for activated protein C-kinase 1 (RACK-1) and pc3n3, which up-regulates endogenous RACK-1, in both Jurkat and W7.2 T cells resulted in inhibition of goniothalamin-induced cell death as assessed by MTT and clonogenic assays. However, overexpression of rFau (antisense sequence to Finkel–Biskis–Reilly murine sarcoma virus-associated ubiquitously expressed gene) in W7.2 cells did not confer resistance to goniothalamin-induced cell death. Etoposide, a clinically used cytotoxic agent, was equipotent in causing cytotoxicity in all the stable transfectants. Assessment of DNA damage by Comet assay revealed goniothalamin-induced DNA strand breaks as early as 1 h in vector control but this effect was inhibited in RACK-1 and pc3n3 stably transfected W7.2 cells. This data demonstrate that RACK-1 plays a crucial role in regulating cell death signalling pathways induced by goniothalamin. PMID:19698770

  19. Clinical applications of mesenchymal stem cells

    PubMed Central

    Kim, Nayoun

    2013-01-01

    Mesenchymal stem cells (MSCs) are self-renewing, multipotent progenitor cells with multilineage potential to differentiate into cell types of mesodermal origin, such as adipocytes, osteocytes, and chondrocytes. In addition, MSCs can migrate to sites of inflammation and exert potent immunosuppressive and anti-inflammatory effects through interactions between lymphocytes associated with both the innate and adaptive immune system. Along with these unique therapeutic properties, their ease of accessibility and expansion suggest that use of MSCs may be a useful therapeutic approach for various disorders. In the clinical setting, MSCs are being explored in trials of various conditions, including orthopedic injuries, graft versus host disease following bone marrow transplantation, cardiovascular diseases, autoimmune diseases, and liver diseases. Furthermore, genetic modification of MSCs to overexpress antitumor genes has provided prospects for clinical use as anticancer therapy. Here, we highlight the currently reported uses of MSCs in clinical trials and discuss their efficacy as well as their limitations. PMID:23864795

  20. Stem cells in cardiac repair.

    PubMed

    Henning, Robert J

    2011-01-01

    Myocardial infarction is the leading cause of death among people in industrialized nations. Although the heart has some ability to regenerate after infarction, myocardial restoration is inadequate. Consequently, investigators are currently exploring the use of human embryonic stem cells (hESCs), skeletal myoblasts and adult bone marrow stem cells to limit infarct size. hESCs are pluripotent cells that can regenerate myocardium in infarcted hearts, attenuate heart remodeling and contribute to left ventricle (LV) systolic force development. Since hESCs can form heart teratomas, investigators are differentiating hESCs toward cardiac progenitor cells prior to transplantation into hearts. Large quantities of hESCs cardiac progenitor cells, however, must be generated, immune rejection must be prevented and grafts must survive over the long term to significantly improve myocardial performance. Transplanted autologous skeletal myoblasts can survive in infarcted myocardium in small numbers, proliferate, differentiate into skeletal myofibers and increase the LV ejection fraction. These cells, however, do not form electromechanical connections with host cardiomyocytes. Consequently, electrical re-entry can occur and cause cardiac arrhythmias. Autologous bone marrow mononuclear cells contain hematopoietic and mesenchymal stem cells. In several meta-analyses, patients with coronary disease who received autologous bone marrow cells by intracoronary injection show significant 3.7% (range: 1.9-5.4%) increases in LV ejection fraction, decreases in LV end-systolic volume of -4.8 ml (range: -1.4 to -8.2 ml) and reductions in infarct size of 5.5% (-1.9 to -9.1%), without experiencing arrhythmias. Bone marrow cells appear to release biologically active factors that limit myocardial damage. Unfortunately, bone marrow cells from patients with chronic diseases propagate poorly and can die prematurely. Substantial challenges must be addressed and resolved to advance the use of stem cells

  1. [Therapeutic use of stem cells. II. Adult stem cells].

    PubMed

    Uzan, Georges

    2004-09-30

    Many degenerative diseases are not curable by means of classical medicine. The long term objective of cell therapy is to treat the patients with their own stem cells that could be either purified from the diseased organ or from "reservoirs" of stem cells such as that constituted by the bone marrow. The existence of stem cells in the organs or reservoirs is now established in vitro and in some cases, in animal models. Numbers of technical problems linked to the scarcity of these cells still delay the clinical use of purified stem cells. However, clinical protocols using heterogeneous cell populations have already started to treat a growing number of diseases. In some case, autologous cells can be used, as it is the case for bone marrow transplantation in blood diseases. Mesenchymal cells, also purified from the bone marrow are currently used in orthopaedic diseases. Because these cells reveal a broad differentiation potential, active research programs explore their possible use for treatment of other diseases. Bone marrow also contains vascular stem cells that could be active in reappearing defective vessels responsible for ischaemic diseases. Indeed, clinical trials in which bone marrow cells are injected in the cardiac muscle of patients with myocardial infarction or in the leg muscle (gastrocnemius) of patients with hind limb ischaemia have already started. Artificial skin prepared from skin biopsies is used for the reconstitution of the derma of severely burned patients. Clinical trials have also started, using allogenic cells. The patients must be treated by immunosuppressive drugs. Neurodegenerative diseases such as Parkinson have been successfully treated by intra-cerebral injection of foetal neurones. Pancreatic islets implanted in the liver have shown to re-establish a normal glycaemia in diabetic patients. However, all these clinical trials use differentiated cells or at least progenitors which display differentiation potential and lifetime much more

  2. Effect of CD133 overexpression on the epithelial-to-mesenchymal transition in oral cancer cell lines.

    PubMed

    Moon, YeonHee; Kim, Donghwi; Sohn, HongMoon; Lim, Wonbong

    2016-06-01

    Oral squamous cell carcinoma (OSCC) is one of the most common cancers in the world. In OSCC, CD133 promotes tumor invasion and metastasis by inducing the epithelial-to-mesenchymal transition (EMT). A small subset of cancer cells known as cancer stem cells (CSCs) are thought to give rise to differentiated tumor cells and to predict tumor recurrence and metastases, i.e., CSCs may be metastatic precursors. In this study, we show that ectopic overexpression of CD133 in OSCC cell lines KB, YD9, and YD10B cells significantly promotes the EMT and acquisition of stemness properties. CSC properties were analyzed by colony-formation assay and measurement of OCT4, SOX2, and NANOG expression, and the EMT was monitored by cell migration, a cell invasion assay, and analysis of E-cadherin, N-cadherin, and vimentin expression. CD133 overexpression led to formation of irregular spheroid colonies consistent with a stem cell phenotype and increased the expression of OCT4, SOX2, NANOG, N-cadherin, and vimentin. Taken together, these findings show that elevated levels of CD133 lead to OSCC invasiveness and metastasis, associated with the upregulation of EMT and stemness markers.

  3. SNEV overexpression extends the life span of human endothelial cells

    SciTech Connect

    Voglauer, Regina; Chang, Martina Wei-Fen; Dampier, Brigitta; Wieser, Matthias; Baumann, Kristin; Sterovsky, Thomas; Schreiber, Martin; Katinger, Hermann; Grillari, Johannes . E-mail: j.grillari@iam.boku.ac.at

    2006-04-01

    In a recent screening for genes downregulated in replicatively senescent human umbilical vein endothelial cells (HUVECs), we have isolated the novel protein SNEV. Since then SNEV has proven as a multifaceted protein playing a role in pre-mRNA splicing, DNA repair, and the ubiquitin/proteosome system. Here, we report that SNEV mRNA decreases in various cell types during replicative senescence, and that it is increased in various immortalized cell lines, as well as in breast tumors, where SNEV transcript levels also correlate with the survival of breast cancer patients. Since these mRNA profiles suggested a role of SNEV in the regulation of cell proliferation, the effect of its overexpression was tested. Thereby, a significant extension of the cellular life span was observed, which was not caused by altered telomerase activity or telomere dynamics but rather by enhanced stress resistance. When SNEV overexpressing cells were treated with bleomycin or bleomycin combined with BSO, inducing DNA damage as well as reactive oxygen species, a significantly lower fraction of apoptotic cells was found in comparison to vector control cells. These data suggest that high levels of SNEV might extend the cellular life span by increasing the resistance to stress or by improving the DNA repair capacity of the cells.

  4. Intestinal Stem Cells: Got Calcium?

    PubMed

    Nászai, Máté; Cordero, Julia B

    2016-02-01

    Calcium ions are well-known intracellular signalling molecules. A new study identifies local cytoplasmic calcium as a central integrator of metabolic and proliferative signals in Drosophila intestinal stem cells. PMID:26859268

  5. Stem cell potential of the mammalian gonad

    PubMed Central

    Liu, Chia-Feng; Barsoum, Ivraym; Gupta, Rupesh; Hofmann, Marie-Claude; Yao, Humphrey Hung-Chang

    2010-01-01

    Stem cells have enormous potential for therapeutic application because of their ability to self-renew and differentiate into different cell types. Gonads, which consist of somatic cells and germ cells, are the only organs capable of transmitting genetic materials to the offspring. Germ-line stem cells and somatic stem cells have been found in the testis; however, the presence of stem cells in the ovary remains controversial. In this review, we discuss studies focusing on whether stem cell properties are present in the different cell types of male and female gonads and their implications on stem cell research. PMID:19482665

  6. Overexpression of neurofilament H disrupts normal cell structure and function

    NASA Technical Reports Server (NTRS)

    Szebenyi, Gyorgyi; Smith, George M.; Li, Ping; Brady, Scott T.

    2002-01-01

    Studying exogenously expressed tagged proteins in live cells has become a standard technique for evaluating protein distribution and function. Typically, expression levels of experimentally introduced proteins are not regulated, and high levels are often preferred to facilitate detection. However, overexpression of many proteins leads to mislocalization and pathologies. Therefore, for normative studies, moderate levels of expression may be more suitable. To understand better the dynamics of intermediate filament formation, transport, and stability in a healthy, living cell, we inserted neurofilament heavy chain (NFH)-green fluorescent protein (GFP) fusion constructs in adenoviral vectors with tetracycline (tet)-regulated promoters. This system allows for turning on or off the synthesis of NFH-GFP at a selected time, for a defined period, in a dose-dependent manner. We used this inducible system for live cell imaging of changes in filament structure and cell shape, motility, and transport associated with increasing NFH-GFP expression. Cells with low to intermediate levels of NFH-GFP were structurally and functionally similar to neighboring, nonexpressing cells. In contrast, overexpression led to pathological alterations in both filament organization and cell function. Copyright 2002 Wiley-Liss, Inc.

  7. Pancreatic stem cells remain unresolved.

    PubMed

    Jiang, Fang-Xu; Morahan, Grant

    2014-12-01

    Diabetes mellitus is caused by absolute (type 1) or relative (type 2) deficiency of insulin-secreting islet β cells. An ideal treatment of diabetes would, therefore, be to replace the lost or deficient β cells, by transplantation of donated islets or differentiated endocrine cells or by regeneration of endogenous islet cells. Due to their ability of unlimited proliferation and differentiation into all functional lineages in our body, including β cells, embryonic stem cells and induced pluripotent stem cells are ideally placed as cell sources for a diabetic transplantation therapy. Unfortunately, the inability to generate functional differentiated islet cells from pluripotent stem cells and the poor availability of donor islets have severely restricted the broad clinical use of the replacement therapy. Therefore, endogenous sources that can be directed to becoming insulin-secreting cells are actively sought after. In particular, any cell types in the developing or adult pancreas that may act as pancreatic stem cells (PSC) would provide an alternative renewable source for endogenous regeneration. In this review, we will summarize the latest progress and knowledge of such PSC, and discuss ways that facilitate the future development of this often controversial, but crucial research.

  8. Overexpression of {alpha}-catenin increases osteoblastic differentiation in mouse mesenchymal C3H10T1/2 cells

    SciTech Connect

    Kim, Dohee; Yang, Jae-Yeon; Shin, Chan Soo

    2009-05-15

    {alpha}- and {beta}-Catenin link cadherins to the actin-based cytoskeleton at adherens junctions and regulate cell-cell adhesion. Although roles of cadherins and canonical Wnt-/{beta}-catenin-signaling in osteoblastic differentiation have been extensively studied, the role of {alpha}-catenin is not known. Murine embryonic mesenchymal stem cells, C3H10T1/2 cells, were transduced with retrovirus encoding {alpha}-catenin (MSCV-{alpha}-catenin-HA-GFP). In the presence of Wnt-3A conditioned medium or osteogenic medium ({beta}-glycerol phosphate and ascorbic acid), cells overexpressing {alpha}-catenin showed enhanced osteoblastic differentiation as measured by alkaline phosphatase (ALP) staining and ALP activity assay compared to cells transduced with empty virus (MSCV-GFP). In addition, mRNA expression of osteocalcin and Runx2 was significantly increased compared to control. Cell aggregation assay revealed that {alpha}-catenin overexpression has significantly increased cell-cell aggregation. However, cellular {beta}-catenin levels (total, cytoplasmic-nuclear ratio) and {beta}-catenin-TCF/LEF transcriptional activity did not change by overexpression of {alpha}-catenin. Knock-down of {alpha}-catenin using siRNA decreased osteoblastic differentiation as measured by ALP assay. These results suggest that {alpha}-catenin overexpression increases osteoblastic differentiation by increasing cell-cell adhesion rather than Wnt-/{beta}-catenin-signaling.

  9. Mesenchymal Stem Cells with Increased Stromal Cell-Derived Factor 1 Expression Enhanced Fracture Healing

    PubMed Central

    Ho, Chih-Yuan; Hua, Jia; Coathup, Melanie; Kalia, Priya; Blunn, Gordon

    2015-01-01

    Treatment of critical size bone defects pose a challenge in orthopedics. Stem cell therapy together with cytokines has the potential to improve bone repair as they cause the migration and homing of stem cells to the defect site. However, the engraftment, participation, and recruitment of other cells within the regenerating tissue are important. To enhance stem cell involvement, this study investigated overexpression of stem cells with stromal cell-derived factor 1 (SDF-1) using an adenovirus. We hypothesized that these engineered cells would effectively increase the migration of native cells to the site of fracture, enhancing bone repair. Before implantation, we showed that SDF-1 secreted by transfected cells increased the migration of nontransfected cells. In a rat defect bone model, bone marrow mesenchymal stem cells overexpressing SDF-1 showed significantly (p=0.003) more new bone formation within the gap and less bone mineral loss at the area adjacent to the defect site during the early bone healing stage. In conclusion, SDF-1 was shown to play an important role in accelerating fracture repair and contributing to bone repair in rat models, by recruiting more host stem cells to the defect site and encouraging osteogenic differentiation and production of bone. PMID:25251779

  10. Targeting Breast Cancer Stem Cells

    PubMed Central

    McDermott, Sean P.; Wicha, Max S.

    2010-01-01

    The cancer stem cell (CSC) hypothesis postulates that tumors are maintained by a self-renewing CSC population that is also capable of differentiating into non-self renewing cell populations that constitute the bulk of the tumor. Although, the CSC hypothesis does not directly address the cell of origin of cancer, it is postulated that tissue-resident stem or progenitors are the most common targets of transformation. Clinically, CSCs are predicted to mediate tumor recurrence after chemo- and radiation-therapy due to the relative inability of these modalities to effectively target CSCs. If this is the case, then CSC must be efficiently targeted to achieve a true cure. Similarities between normal and malignant stem cells, at the levels of cell-surface proteins, molecular pathways, cell cycle quiescence, and microRNA signaling present challenges in developing CSC-specific therapeutics. Approaches to targeting CSCs include the development of agents targeting known stem cell regulatory pathways as well as unbiased high-throughput siRNA or small-molecule screening. Based on studies of pathways present in normal stem cells, recent work has identified potential “Achilles heals” of CSC, whereas unbiased screening provides opportunities to identify new pathways utilized by CSC as well as develop potential therapeutic agents. Here, we review both approaches and their potential to effectively target breast CSC. PMID:20599450

  11. Dormancy activation mechanism of tracheal stem cells

    PubMed Central

    Li, Xin; Xu, Jing-xian; Jia, Xin-Shan; Li, Wen-ya; Han, Yi-chen; Wang, En-hua; Li, Fang

    2016-01-01

    Accurate markers and molecular mechanisms of stem cell dormancy and activation are poorly understood. In this study, the anti-cancer drug, 5-fluorouracil, was used to selectively kill proliferating cells of human bronchial epithelial (HBE) cell line. This method can enrich and purify stem cell population. The dormant versus active status of stem cells was determined by phosphorylation of RNAp II Ser2. The surviving stem cells were cultured to form stem cell spheres expressing stem cell markers and transplanted into nude mice to form a teratoma. The results demonstrated the properties of stem cells and potential for multi-directional differentiation. Bisulfite sequencing polymerase chain reaction showed that demethylation of the Sox2 promoter by 5-FU resulted in Sox2 expression in the dormant stem cells. This study shows that the dormancy and activation of HBE stem cells is closely related to epigenetic modification. PMID:27009861

  12. Stem cell regulation: Implications when differentiated cells regulate symmetric stem cell division.

    PubMed

    Høyem, Marte Rørvik; Måløy, Frode; Jakobsen, Per; Brandsdal, Bjørn Olav

    2015-09-01

    We use a mathematical model to show that if symmetric stem cell division is regulated by differentiated cells, then changes in the population dynamics of the differentiated cells can lead to changes in the population dynamics of the stem cells. More precisely, the relative fitness of the stem cells can be affected by modifying the death rate of the differentiated cells. This result is interesting because stem cells are less sensitive than differentiated cells to environmental factors, such as medical therapy. Our result implies that stem cells can be manipulated indirectly by medical treatments that target the differentiated cells. PMID:25997796

  13. Engineering stem cell niches in bioreactors

    PubMed Central

    Liu, Meimei; Liu, Ning; Zang, Ru; Li, Yan; Yang, Shang-Tian

    2013-01-01

    Stem cells, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells and amniotic fluid stem cells have the potential to be expanded and differentiated into various cell types in the body. Efficient differentiation of stem cells with the desired tissue-specific function is critical for stem cell-based cell therapy, tissue engineering, drug discovery and disease modeling. Bioreactors provide a great platform to regulate the stem cell microenvironment, known as “niches”, to impact stem cell fate decision. The niche factors include the regulatory factors such as oxygen, extracellular matrix (synthetic and decellularized), paracrine/autocrine signaling and physical forces (i.e., mechanical force, electrical force and flow shear). The use of novel bioreactors with precise control and recapitulation of niche factors through modulating reactor operation parameters can enable efficient stem cell expansion and differentiation. Recently, the development of microfluidic devices and microbioreactors also provides powerful tools to manipulate the stem cell microenvironment by adjusting flow rate and cytokine gradients. In general, bioreactor engineering can be used to better modulate stem cell niches critical for stem cell expansion, differentiation and applications as novel cell-based biomedicines. This paper reviews important factors that can be more precisely controlled in bioreactors and their effects on stem cell engineering. PMID:24179601

  14. Stem Cells and Liver Regeneration

    PubMed Central

    DUNCAN, ANDREW W.; DORRELL, CRAIG; GROMPE, MARKUS

    2011-01-01

    One of the defining features of the liver is the capacity to maintain a constant size despite injury. Although the precise molecular signals involved in the maintenance of liver size are not completely known, it is clear that the liver delicately balances regeneration with overgrowth. Mammals, for example, can survive surgical removal of up to 75% of the total liver mass. Within 1 week after liver resection, the total number of liver cells is restored. Moreover, liver overgrowth can be induced by a variety of signals, including hepatocyte growth factor or peroxisome proliferators; the liver quickly returns to its normal size when the proliferative signal is removed. The extent to which liver stem cells mediate liver regeneration has been hotly debated. One of the primary reasons for this controversy is the use of multiple definitions for the hepatic stem cell. Definitions for the liver stem cell include the following: (1) cells responsible for normal tissue turnover, (2) cells that give rise to regeneration after partial hepatectomy, (3) cells responsible for progenitor-dependent regeneration, (4) cells that produce hepatocyte and bile duct epithelial phenotypes in vitro, and (5) transplantable liver-repopulating cells. This review will consider liver stem cells in the context of each definition. PMID:19470389

  15. Dental Stem Cell in Tooth Development and Advances of Adult Dental Stem Cell in Regenerative Therapies.

    PubMed

    Tan, Jiali; Xu, Xin; Lin, Jiong; Fan, Li; Zheng, Yuting; Kuang, Wei

    2015-01-01

    Stem cell-based therapies are considered as a promising treatment for many clinical usage such as tooth regeneration, bone repairation, spinal cord injury, and so on. However, the ideal stem cell for stem cell-based therapy still remains to be elucidated. In the past decades, several types of stem cells have been isolated from teeth, including dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), dental follicle progenitor stem cells (DFPCs) and stem cells from apical papilla (SCAP), which may be a good source for stem cell-based therapy in certain disease, especially when they origin from neural crest is considered. In this review, the specific characteristics and advantages of the adult dental stem cell population will be summarized and the molecular mechanisms of the differentiation of dental stem cell during tooth development will be also discussed.

  16. Stem cells and kidney regeneration.

    PubMed

    Chou, Yu-Hsiang; Pan, Szu-Yu; Yang, Chian-Huei; Lin, Shuei-Liong

    2014-04-01

    Kidney disease is an escalating burden all over the world. In addition to preventing kidney injury, regenerating damaged renal tissue is as important as to retard the progression of chronic kidney disease to end stage renal disease. Although the kidney is a delicate organ and has only limited regenerative capacity compared to the other organs, an increasing understanding of renal development and renal reprogramming has kindled the prospects of regenerative options for kidney disease. Here, we will review the advances in the kidney regeneration including the manipulation of renal tubular cells, fibroblasts, endothelial cells, and macrophages in renal disease. Several types of stem cells, such as bone marrow-derived cells, adipocyte-derived mesenchymal stem cells, embryonic stem cells, and induced pluripotent stem cells are also applied for renal regeneration. Endogenous or lineage reprogrammed renal progenitor cells represent an attractive possibility for differentiation into multiple renal cell types. Angiogenesis can ameliorate hypoxia and renal fibrosis. Based on these studies and knowledge, we hope to innovate more reliable pharmacological or biotechnical methods for kidney regeneration medicine.

  17. Pluripotent stem cells from germ cells.

    PubMed

    Kerr, Candace L; Shamblott, Michael J; Gearhart, John D

    2006-01-01

    To date, stem cells have been derived from three sources of germ cells. These include embryonic germ cells (EGCs), embryonal carcinoma cells (ECCs), and multipotent germ line stem cells (GSCs). EGCs are derived from primordial germ cells that arise in the late embryonic and early fetal period of development. ECCs are derived from adult testicular tumors whereas GSCs have been derived by culturing spermatogonial stem cells from mouse neonates and adults. For each of these lines, their pluripotency has been demonstrated by their ability to differentiate into cell types derived from the three germ layers in vitro and in vivo and in chimeric animals, including germ line transmission. These germ line-derived stem cells have been generated from many species including human, mice, porcine, and chicken albeit with only slight modifications. This chapter describes general considerations regarding critical aspects of their derivation compared with their counterpart, embryonic stem cells (ESCs). Detailed protocols for EGC derivation and maintenance from human and mouse primordial germ cells (PGCs) will be presented.

  18. Overexpression of Arabidopsis VIT1 increases accumulation of iron in cassava roots and stems.

    PubMed

    Narayanan, Narayanan; Beyene, Getu; Chauhan, Raj Deepika; Gaitán-Solis, Eliana; Grusak, Michael A; Taylor, Nigel; Anderson, Paul

    2015-11-01

    Iron is extremely abundant in the soil, but its uptake in plants is limited due to low solubility in neutral or alkaline soils. Plants can rely on rhizosphere acidification to increase iron solubility. AtVIT1 was previously found to be involved in mediating vacuolar sequestration of iron, which indicates a potential application for iron biofortification in crop plants. Here, we have overexpressed AtVIT1 in the starchy root crop cassava using a patatin promoter. Under greenhouse conditions, iron levels in mature cassava storage roots showed 3-4 times higher values when compared with wild-type plants. Significantly, the expression of AtVIT1 showed a positive correlation with the increase in iron concentration of storage roots. Conversely, young leaves of AtVIT1 transgenic plants exhibit characteristics of iron deficiency such as interveinal chlorosis of leaves (yellowing) and lower iron concentration when compared with the wild type plants. Interestingly, the AtVIT1 transgenic plants showed 4 and 16 times higher values of iron concentration in the young stem and stem base tissues, respectively. AtVIT1 transgenic plants also showed 2-4 times higher values of iron content when compared with wild-type plants, with altered partitioning of iron between source and sink tissues. These results demonstrate vacuolar iron sequestration as a viable transgenic strategy to biofortify crops and to help eliminate micronutrient malnutrition in at-risk human populations.

  19. Overexpression of Arabidopsis VIT1 increases accumulation of iron in cassava roots and stems.

    PubMed

    Narayanan, Narayanan; Beyene, Getu; Chauhan, Raj Deepika; Gaitán-Solis, Eliana; Grusak, Michael A; Taylor, Nigel; Anderson, Paul

    2015-11-01

    Iron is extremely abundant in the soil, but its uptake in plants is limited due to low solubility in neutral or alkaline soils. Plants can rely on rhizosphere acidification to increase iron solubility. AtVIT1 was previously found to be involved in mediating vacuolar sequestration of iron, which indicates a potential application for iron biofortification in crop plants. Here, we have overexpressed AtVIT1 in the starchy root crop cassava using a patatin promoter. Under greenhouse conditions, iron levels in mature cassava storage roots showed 3-4 times higher values when compared with wild-type plants. Significantly, the expression of AtVIT1 showed a positive correlation with the increase in iron concentration of storage roots. Conversely, young leaves of AtVIT1 transgenic plants exhibit characteristics of iron deficiency such as interveinal chlorosis of leaves (yellowing) and lower iron concentration when compared with the wild type plants. Interestingly, the AtVIT1 transgenic plants showed 4 and 16 times higher values of iron concentration in the young stem and stem base tissues, respectively. AtVIT1 transgenic plants also showed 2-4 times higher values of iron content when compared with wild-type plants, with altered partitioning of iron between source and sink tissues. These results demonstrate vacuolar iron sequestration as a viable transgenic strategy to biofortify crops and to help eliminate micronutrient malnutrition in at-risk human populations. PMID:26475197

  20. DNA methylation and hydroxymethylation in stem cells.

    PubMed

    Cheng, Ying; Xie, Nina; Jin, Peng; Wang, Tao

    2015-06-01

    In mammals, DNA methylation and hydroxymethylation are specific epigenetic mechanisms that can contribute to the regulation of gene expression and cellular functions. DNA methylation is important for the function of embryonic stem cells and adult stem cells (such as haematopoietic stem cells, neural stem cells and germline stem cells), and changes in DNA methylation patterns are essential for successful nuclear reprogramming. In the past several years, the rediscovery of hydroxymethylation and the TET enzymes expanded our insights tremendously and uncovered more dynamic aspects of cytosine methylation regulation. Here, we review the current knowledge and highlight the most recent advances in DNA methylation and hydroxymethylation in embryonic stem cells, induced pluripotent stem cells and several well-studied adult stems cells. Our current understanding of stem cell epigenetics and new advances in the field will undoubtedly stimulate further clinical applications of regenerative medicine in the future.

  1. Stem cells' exodus: a journey to immortality.

    PubMed

    Zhou, Yi; Lewallen, Michelle; Xie, Ting

    2013-01-28

    Stem cell niches provide a regulatory microenvironment that retains stem cells and promotes self-renewal. Recently in Developmental Cell, Rinkevich et al. (2013) showed that cell islands (CIs) of Botryllus schlosseri, a colonial chordate, provide niches for maintaining cycling stem cells that migrate from degenerated CIs to newly formed buds.

  2. Human stem cell ethics: beyond the embryo.

    PubMed

    Sugarman, Jeremy

    2008-06-01

    Human embryonic stem cell research has elicited powerful debates about the morality of destroying human embryos. However, there are important ethical issues related to stem cell research that are unrelated to embryo destruction. These include particular issues involving different types of cells used, the procurement of such cells, in vivo use of stem cells, intellectual property, and conflicts of interest.

  3. Stem-cell ecology and stem cells in motion

    PubMed Central

    Scadden, David T.

    2008-01-01

    This review highlights major scientific developments over the past 50 years or so in concepts related to stem-cell ecology and to stem cells in motion. Many thorough and eloquent reviews have been presented in the last 5 years updating progress in these issues. Some paradigms have been challenged, others validated, or new ones brought to light. In the present review, we will confine our remarks to the historical development of progress. In doing so, we will refrain from a detailed analysis of controversial data, emphasizing instead widely accepted views and some challenging novel ones. PMID:18398055

  4. PIM1 kinase as a promise of targeted therapy in prostate cancer stem cells

    PubMed Central

    XIE, YINGQIU; BAYAKHMETOV, SAMAT

    2016-01-01

    Since the last decade, the PIM family serine/threonine kinases have become a focus in cancer research. Numerous clinical data supports that overexpression of PIM1 is associated with tumor formation in various tissues. However, little is known regarding the function of PIM1 in cancer stem cells. In cancer cells, PIM1 has essential roles in the regulation of the cell cycle, cell proliferation, cell survival and multiple drug resistance. In stem cells, PIM1 kinase exhibits a significant function in stem cell proliferation, self-renewal and expansion. Thus, PIM1 shows a great promise in cancer therapy by targeting stem cells. Furthermore, it is imperative to investigate Pim-1 targeting in cancer stem cells by applicable inhibitors for improving future outcomes. The present review investigated the potential of PIM1 as a therapy target in prostate cancer stem cells. PMID:26835011

  5. MicroRNA-153/Nrf-2/GPx1 pathway regulates radiosensitivity and stemness of glioma stem cells via reactive oxygen species

    PubMed Central

    Yang, Wei; Shen, Yueming; Wei, Jing; Liu, Fenju

    2015-01-01

    Glioma stem cells (GSCs) exhibit stem cell properties and high resistance to radiotherapy. The main aim of our study was to determine the roles of ROS in radioresistance and stemness of GSCs. We found that microRNA (miR)-153 was down-regulated and its target gene nuclear factor-erythroid 2-related factor-2 (Nrf-2) was up-regulated in GSCs compared with that of non-GSCs glioma cells. The enhanced Nrf-2 expression increased glutathione peroxidase 1 (GPx1) transcription and decreased ROS level leading to radioresistance of GSCs. MiR-153 overexpression resulted in increased ROS production and radiosensitization of GSCs. Moreover, miR-153 overexpression led to decreased neurosphere formation capacity and stem cell marker expression, and induced differentiation through ROS-mediated activation of p38 MAPK in GSCs. Nrf-2 overexpression rescued the decreased stemness and radioresistance resulting from miR-153 overexpression in GSCs. In addition, miR-153 overexpression reduced tumorigenic capacity of GSCs and increased survival in mice bearing human GSCs. These findings demonstrated that miR-153 overexpression decreased radioresistance and stemness of GSCs through targeting Nrf-2/GPx1/ROS pathway. PMID:26124081

  6. Introduction to stem cells and regenerative medicine.

    PubMed

    Kolios, George; Moodley, Yuben

    2013-01-01

    Stem cells are a population of undifferentiated cells characterized by the ability to extensively proliferate (self-renewal), usually arise from a single cell (clonal), and differentiate into different types of cells and tissue (potent). There are several sources of stem cells with varying potencies. Pluripotent cells are embryonic stem cells derived from the inner cell mass of the embryo and induced pluripotent cells are formed following reprogramming of somatic cells. Pluripotent cells can differentiate into tissue from all 3 germ layers (endoderm, mesoderm, and ectoderm). Multipotent stem cells may differentiate into tissue derived from a single germ layer such as mesenchymal stem cells which form adipose tissue, bone, and cartilage. Tissue-resident stem cells are oligopotent since they can form terminally differentiated cells of a specific tissue. Stem cells can be used in cellular therapy to replace damaged cells or to regenerate organs. In addition, stem cells have expanded our understanding of development as well as the pathogenesis of disease. Disease-specific cell lines can also be propagated and used in drug development. Despite the significant advances in stem cell biology, issues such as ethical controversies with embryonic stem cells, tumor formation, and rejection limit their utility. However, many of these limitations are being bypassed and this could lead to major advances in the management of disease. This review is an introduction to the world of stem cells and discusses their definition, origin, and classification, as well as applications of these cells in regenerative medicine.

  7. Common stemness regulators of embryonic and cancer stem cells.

    PubMed

    Hadjimichael, Christiana; Chanoumidou, Konstantina; Papadopoulou, Natalia; Arampatzi, Panagiota; Papamatheakis, Joseph; Kretsovali, Androniki

    2015-10-26

    Pluripotency of embryonic stem cells (ESCs) and induced pluripotent stem cells is regulated by a well characterized gene transcription circuitry. The circuitry is assembled by ESC specific transcription factors, signal transducing molecules and epigenetic regulators. Growing understanding of stem-like cells, albeit of more complex phenotypes, present in tumors (cancer stem cells), provides a common conceptual and research framework for basic and applied stem cell biology. In this review, we highlight current results on biomarkers, gene signatures, signaling pathways and epigenetic regulators that are common in embryonic and cancer stem cells. We discuss their role in determining the cell phenotype and finally, their potential use to design next generation biological and pharmaceutical approaches for regenerative medicine and cancer therapies.

  8. Common stemness regulators of embryonic and cancer stem cells

    PubMed Central

    Hadjimichael, Christiana; Chanoumidou, Konstantina; Papadopoulou, Natalia; Arampatzi, Panagiota; Papamatheakis, Joseph; Kretsovali, Androniki

    2015-01-01

    Pluripotency of embryonic stem cells (ESCs) and induced pluripotent stem cells is regulated by a well characterized gene transcription circuitry. The circuitry is assembled by ESC specific transcription factors, signal transducing molecules and epigenetic regulators. Growing understanding of stem-like cells, albeit of more complex phenotypes, present in tumors (cancer stem cells), provides a common conceptual and research framework for basic and applied stem cell biology. In this review, we highlight current results on biomarkers, gene signatures, signaling pathways and epigenetic regulators that are common in embryonic and cancer stem cells. We discuss their role in determining the cell phenotype and finally, their potential use to design next generation biological and pharmaceutical approaches for regenerative medicine and cancer therapies. PMID:26516408

  9. Cancer stem cell signaling pathways.

    PubMed

    Matsui, William H

    2016-09-01

    Tissue development and homeostasis are governed by the actions of stem cells. Multipotent cells are capable of self-renewal during the course of one's lifetime. The accurate and appropriate regulation of stem cell functions is absolutely critical for normal biological activity. Several key developmental or signaling pathways have been shown to play essential roles in this regulatory capacity. Specifically, the Janus-activated kinase/signal transducer and activator of transcription, Hedgehog, Wnt, Notch, phosphatidylinositol 3-kinase/phosphatase and tensin homolog, and nuclear factor-κB signaling pathways have all been shown experimentally to mediate various stem cell properties, such as self-renewal, cell fate decisions, survival, proliferation, and differentiation. Unsurprisingly, many of these crucial signaling pathways are dysregulated in cancer. Growing evidence suggests that overactive or abnormal signaling within and among these pathways may contribute to the survival of cancer stem cells (CSCs). CSCs are a relatively rare population of cancer cells capable of self-renewal, differentiation, and generation of serially transplantable heterogeneous tumors of several types of cancer. PMID:27611937

  10. PrPC from stem cells to cancer

    PubMed Central

    Martin-Lannerée, Séverine; Hirsch, Théo Z.; Hernandez-Rapp, Julia; Halliez, Sophie; Vilotte, Jean-Luc; Launay, Jean-Marie; Mouillet-Richard, Sophie

    2014-01-01

    The cellular prion protein PrPC was initially discovered as the normal counterpart of the pathological scrapie prion protein PrPSc, the main component of the infectious agent of Transmissible Spongiform Encephalopathies. While clues as to the physiological function of this ubiquitous protein were greatly anticipated from the development of knockout animals, PrP-null mice turned out to be viable and to develop without major phenotypic abnormalities. Notwithstanding, the discovery that hematopoietic stem cells from PrP-null mice have impaired long-term repopulating potential has set the stage for investigating into the role of PrPC in stem cell biology. A wealth of data have now exemplified that PrPC is expressed in distinct types of stem cells and regulates their self-renewal as well as their differentiation potential. A role for PrPC in the fate restriction of embryonic stem cells has further been proposed. Paralleling these observations, an overexpression of PrPC has been documented in various types of tumors. In line with the contribution of PrPC to stemness and to the proliferation of cancer cells, PrPC was recently found to be enriched in subpopulations of tumor-initiating cells. In the present review, we summarize the current knowledge of the role played by PrPC in stem cell biology and discuss how the subversion of its function may contribute to cancer progression. PMID:25364760

  11. Noggin 1 overexpression in retinal progenitors affects bipolar cell generation.

    PubMed

    Messina, Andrea; Bridi, Simone; Bozza, Angela; Bozzi, Yuri; Baudet, Marie-Laure; Casarosa, Simona

    2016-01-01

    Waves of Bone Morphogenetic Proteins (BMPs) and their antagonists are present during initial eye development, but their possible roles in retinogenesis are still unknown. We have recently shown that noggin 1, a BMP antagonist, renders pluripotent cells able to differentiate into retinal precursors, and might be involved in the maintenance of retinal structures in the adult vertebrate eye. Here, we report that noggin 1, differently from noggin 2 and noggin 4, is expressed during all phases of Xenopus laevis retinal development. Gain-of-function experiments by electroporation in the optic vesicle show that overexpression of noggin 1 significantly decreases the number of bipolar cells in the inner nuclear layer of the retina, without significantly affecting the generation of the other retinal cell types. Our data suggest that BMP signaling could be involved in the differentiation of retinal progenitors into specific retinal subtypes during late phases of vertebrate retinal development. PMID:27389985

  12. Over-expression of secreted proteins from mammalian cell lines

    PubMed Central

    Dalton, Annamarie C; Barton, William A

    2014-01-01

    Secreted mammalian proteins require the development of robust protein over-expression systems for crystallographic and biophysical studies of protein function. Due to complex disulfide bonds and distinct glycosylation patterns preventing folding and expression in prokaryotic expression hosts, many secreted proteins necessitate production in more complex eukaryotic expression systems. Here, we elaborate on the methods used to obtain high yields of purified secreted proteins from transiently or stably transfected mammalian cell lines. Among the issues discussed are the selection of appropriate expression vectors, choice of signal sequences for protein secretion, availability of fusion tags for enhancing protein stability and purification, choice of cell line, and the large-scale growth of cells in a variety of formats. PMID:24510886

  13. Stem cells sources for intervertebral disc regeneration.

    PubMed

    Vadalà, Gianluca; Russo, Fabrizio; Ambrosio, Luca; Loppini, Mattia; Denaro, Vincenzo

    2016-05-26

    Intervertebral disc regeneration field is rapidly growing since disc disorders represent a major health problem in industrialized countries with very few possible treatments. Indeed, current available therapies are symptomatic, and surgical procedures consist in disc removal and spinal fusion, which is not immune to regardable concerns about possible comorbidities, cost-effectiveness, secondary risks and long-lasting outcomes. This review paper aims to share recent advances in stem cell therapy for the treatment of intervertebral disc degeneration. In literature the potential use of different adult stem cells for intervertebral disc regeneration has already been reported. Bone marrow mesenchymal stromal/stem cells, adipose tissue derived stem cells, synovial stem cells, muscle-derived stem cells, olfactory neural stem cells, induced pluripotent stem cells, hematopoietic stem cells, disc stem cells, and embryonic stem cells have been studied for this purpose either in vitro or in vivo. Moreover, several engineered carriers (e.g., hydrogels), characterized by full biocompatibility and prompt biodegradation, have been designed and combined with different stem cell types in order to optimize the local and controlled delivery of cellular substrates in situ. The paper overviews the literature discussing the current status of our knowledge of the different stem cells types used as a cell-based therapy for disc regeneration.

  14. Stem cells sources for intervertebral disc regeneration

    PubMed Central

    Vadalà, Gianluca; Russo, Fabrizio; Ambrosio, Luca; Loppini, Mattia; Denaro, Vincenzo

    2016-01-01

    Intervertebral disc regeneration field is rapidly growing since disc disorders represent a major health problem in industrialized countries with very few possible treatments. Indeed, current available therapies are symptomatic, and surgical procedures consist in disc removal and spinal fusion, which is not immune to regardable concerns about possible comorbidities, cost-effectiveness, secondary risks and long-lasting outcomes. This review paper aims to share recent advances in stem cell therapy for the treatment of intervertebral disc degeneration. In literature the potential use of different adult stem cells for intervertebral disc regeneration has already been reported. Bone marrow mesenchymal stromal/stem cells, adipose tissue derived stem cells, synovial stem cells, muscle-derived stem cells, olfactory neural stem cells, induced pluripotent stem cells, hematopoietic stem cells, disc stem cells, and embryonic stem cells have been studied for this purpose either in vitro or in vivo. Moreover, several engineered carriers (e.g., hydrogels), characterized by full biocompatibility and prompt biodegradation, have been designed and combined with different stem cell types in order to optimize the local and controlled delivery of cellular substrates in situ. The paper overviews the literature discussing the current status of our knowledge of the different stem cells types used as a cell-based therapy for disc regeneration. PMID:27247704

  15. Stem cells sources for intervertebral disc regeneration.

    PubMed

    Vadalà, Gianluca; Russo, Fabrizio; Ambrosio, Luca; Loppini, Mattia; Denaro, Vincenzo

    2016-05-26

    Intervertebral disc regeneration field is rapidly growing since disc disorders represent a major health problem in industrialized countries with very few possible treatments. Indeed, current available therapies are symptomatic, and surgical procedures consist in disc removal and spinal fusion, which is not immune to regardable concerns about possible comorbidities, cost-effectiveness, secondary risks and long-lasting outcomes. This review paper aims to share recent advances in stem cell therapy for the treatment of intervertebral disc degeneration. In literature the potential use of different adult stem cells for intervertebral disc regeneration has already been reported. Bone marrow mesenchymal stromal/stem cells, adipose tissue derived stem cells, synovial stem cells, muscle-derived stem cells, olfactory neural stem cells, induced pluripotent stem cells, hematopoietic stem cells, disc stem cells, and embryonic stem cells have been studied for this purpose either in vitro or in vivo. Moreover, several engineered carriers (e.g., hydrogels), characterized by full biocompatibility and prompt biodegradation, have been designed and combined with different stem cell types in order to optimize the local and controlled delivery of cellular substrates in situ. The paper overviews the literature discussing the current status of our knowledge of the different stem cells types used as a cell-based therapy for disc regeneration. PMID:27247704

  16. Stem cell transplantation for neuroblastoma.

    PubMed

    Fish, J D; Grupp, S A

    2008-01-01

    High-risk neuroblastoma is a childhood malignancy with a poor prognosis. Gradual improvements in survival have correlated with therapeutic intensity, and the ability to harvest, process and store autologous hematopoietic stem cells has allowed for dose intensification beyond marrow tolerance. The use of high-dose chemotherapy with autologous hematopoietic stem cell rescue in consolidation has resulted in improvements in survival, although further advances are still needed. Newer approaches to SCT and supportive care, most notably the transition to PBSC, have resulted in further improvement in survival and decreases in treatment-related mortality. Research into experimental approaches to hematopoietic SCT is ongoing.

  17. Therapeutic Efficacy of Stem Cells Transplantation in Diabetes: Role of Heme Oxygenase

    PubMed Central

    Raffaele, Marco; Li Volti, Giovanni; Barbagallo, Ignazio A.; Vanella, Luca

    2016-01-01

    The growing data obtained from in vivo studies and clinical trials demonstrated the benefit of adult stem cells transplantation in diabetes; although an important limit is represented by their survival after the transplant. To this regard, recent reports suggest that genetic manipulation of stem cells prior to transplantation can lead to enhanced survival and better engraftment. The following review proposes to stimulate interest in the role of heme oxygenase-1 over-expression on transplantation of stem cells in diabetes, focusing on the clinical potential of heme oxygenase protein and activity to restore tissue damage and/or to improve the immunomodulatory properties of transplanted stem cells. PMID:27547752

  18. The regulatory niche of intestinal stem cells.

    PubMed

    Sailaja, Badi Sri; He, Xi C; Li, Linheng

    2016-09-01

    The niche constitutes a unique category of cells that support the microenvironment for the maintenance and self-renewal of stem cells. Intestinal stem cells reside at the base of the crypt, which contains adjacent epithelial cells, stromal cells and smooth muscle cells, and soluble and cell-associated growth and differentiation factors. We summarize here recent advances in our understanding of the crucial role of the niche in regulating stem cells. The stem cell niche maintains a balance among quiescence, proliferation and regeneration of intestinal stem cells after injury. Mesenchymal cells, Paneth cells, immune cells, endothelial cells and neural cells are important regulatory components that secrete niche ligands, growth factors and cytokines. Intestinal homeostasis is regulated by niche signalling pathways, specifically Wnt, bone morphogenetic protein, Notch and epidermal growth factor. These insights into the regulatory stem cell niche during homeostasis and post-injury regeneration offer the potential to accelerate development of therapies for intestine-related disorders.

  19. The regulatory niche of intestinal stem cells.

    PubMed

    Sailaja, Badi Sri; He, Xi C; Li, Linheng

    2016-09-01

    The niche constitutes a unique category of cells that support the microenvironment for the maintenance and self-renewal of stem cells. Intestinal stem cells reside at the base of the crypt, which contains adjacent epithelial cells, stromal cells and smooth muscle cells, and soluble and cell-associated growth and differentiation factors. We summarize here recent advances in our understanding of the crucial role of the niche in regulating stem cells. The stem cell niche maintains a balance among quiescence, proliferation and regeneration of intestinal stem cells after injury. Mesenchymal cells, Paneth cells, immune cells, endothelial cells and neural cells are important regulatory components that secrete niche ligands, growth factors and cytokines. Intestinal homeostasis is regulated by niche signalling pathways, specifically Wnt, bone morphogenetic protein, Notch and epidermal growth factor. These insights into the regulatory stem cell niche during homeostasis and post-injury regeneration offer the potential to accelerate development of therapies for intestine-related disorders. PMID:27060879

  20. Neoplastic human embryonic stem cells as a model of radiation resistance of human cancer stem cells

    PubMed Central

    Dingwall, Steve; Lee, Jung Bok; Guezguez, Borhane; Fiebig, Aline; McNicol, Jamie; Boreham, Douglas; Collins, Tony J.; Bhatia, Mick

    2015-01-01

    Studies have implicated that a small sub-population of cells within a tumour, termed cancer stem cells (CSCs), have an enhanced capacity for tumour formation in multiple cancers and may be responsible for recurrence of the disease after treatment, including radiation. Although comparisons have been made between CSCs and bulk-tumour, the more important comparison with respect to therapy is between tumour-sustaining CSC versus normal stem cells that maintain the healthy tissue. However, the absence of normal known counterparts for many CSCs has made it difficult to compare the radiation responses of CSCs with the normal stem cells required for post-radiotherapy tissue regeneration and the maintenance of tissue homeostasis. Here we demonstrate that transformed human embryonic stem cells (t-hESCs), showing features of neoplastic progression produce tumours resistant to radiation relative to their normal counterpart upon injection into immune compromised mice. We reveal that t-hESCs have a reduced capacity for radiation induced cell death via apoptosis and exhibit altered cell cycle arrest relative to hESCs in vitro. t-hESCs have an increased expression of BclXL in comparison to their normal counterparts and re-sensitization of t-hESCs to radiation upon addition of BH3-only mimetic ABT737, suggesting that overexpression of BclXL underpins t-hESC radiation insensitivity. Using this novel discovery platform to investigate radiation resistance in human CSCs, our study indicates that chemotherapy targeting Bcl2-family members may prove to be an adjuvant to radiotherapy capable of targeting CSCs. PMID:26082437

  1. Neoplastic human embryonic stem cells as a model of radiation resistance of human cancer stem cells.

    PubMed

    Dingwall, Steve; Lee, Jung Bok; Guezguez, Borhane; Fiebig, Aline; McNicol, Jamie; Boreham, Douglas; Collins, Tony J; Bhatia, Mick

    2015-09-01

    Studies have implicated that a small sub-population of cells within a tumour, termed cancer stem cells (CSCs), have an enhanced capacity for tumour formation in multiple cancers and may be responsible for recurrence of the disease after treatment, including radiation. Although comparisons have been made between CSCs and bulk-tumour, the more important comparison with respect to therapy is between tumour-sustaining CSC versus normal stem cells that maintain the healthy tissue. However, the absence of normal known counterparts for many CSCs has made it difficult to compare the radiation responses of CSCs with the normal stem cells required for post-radiotherapy tissue regeneration and the maintenance of tissue homeostasis. Here we demonstrate that transformed human embryonic stem cells (t-hESCs), showing features of neoplastic progression produce tumours resistant to radiation relative to their normal counterpart upon injection into immune compromised mice. We reveal that t-hESCs have a reduced capacity for radiation induced cell death via apoptosis and exhibit altered cell cycle arrest relative to hESCs in vitro. t-hESCs have an increased expression of BclXL in comparison to their normal counterparts and re-sensitization of t-hESCs to radiation upon addition of BH3-only mimetic ABT737, suggesting that overexpression of BclXL underpins t-hESC radiation insensitivity. Using this novel discovery platform to investigate radiation resistance in human CSCs, our study indicates that chemotherapy targeting Bcl2-family members may prove to be an adjuvant to radiotherapy capable of targeting CSCs.

  2. Generation of stomach tissue from mouse embryonic stem cells.

    PubMed

    Noguchi, Taka-aki K; Ninomiya, Naoto; Sekine, Mari; Komazaki, Shinji; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

    2015-08-01

    Successful pluripotent stem cell differentiation methods have been developed for several endoderm-derived cells, including hepatocytes, β-cells and intestinal cells. However, stomach lineage commitment from pluripotent stem cells has remained a challenge, and only antrum specification has been demonstrated. We established a method for stomach differentiation from embryonic stem cells by inducing mesenchymal Barx1, an essential gene for in vivo stomach specification from gut endoderm. Barx1-inducing culture conditions generated stomach primordium-like spheroids, which differentiated into mature stomach tissue cells in both the corpus and antrum by three-dimensional culture. This embryonic stem cell-derived stomach tissue (e-ST) shared a similar gene expression profile with adult stomach, and secreted pepsinogen as well as gastric acid. Furthermore, TGFA overexpression in e-ST caused hypertrophic mucus and gastric anacidity, which mimicked Ménétrier disease in vitro. Thus, in vitro stomach tissue derived from pluripotent stem cells mimics in vivo development and can be used for stomach disease models.

  3. miR-203 inhibits the proliferation and self-renewal of esophageal cancer stem-like cells by suppressing stem renewal factor Bmi-1.

    PubMed

    Yu, Xiying; Jiang, Xingran; Li, Hongxia; Guo, Liping; Jiang, Wei; Lu, Shih-Hsin

    2014-03-15

    Cancer stem-like cells exist in many malignancies and several stem cell-related genes and microRNAs, such as Bmi-1 and miR-203, have been identified as cancer stem-like cell regulators using gene microarray or sequencing analysis. Previously, we used side population (SP) sorting to enrich cancer stem-like cells from esophageal squamous cell carcinoma (ESCC) cell line EC9706. Our results demonstrated that EC9706 SP cells shared common features of cancer stem-like cells. In this study, we examined the expression of Bmi-1 and miR-203 in ESCC SP and non-SP (NSP) cells. Our results showed that, when compared with NSP cells, Bmi-1 was up-regulated and miR-203 was down-regulated in SP cells. During the differentiation from SP to NSP cells, the expression levels of Bmi-1 were gradually decreased. Overexpression of miR-203 resulted in a significant reduction of endogenous Bmi-1 protein level in EC9706 cells. SP and NSP analyses revealed that the SP cell fraction was markedly decreased in miR-203 overexpressed cells. miR-203 overexpressed cells also showed a significant reduction in colony formation, which was resistant to chemotherapeutic drug treatment and tumorigenicity in nude mice. Rescue experiments demonstrated that ectopic expression of Bmi-1 in miR-203 overexpressed cells increased the SP fraction and restored cell proliferation. Taken together, these results indicated that stem renewal factor Bmi-1 was a direct target of miR-203. The regulation of Bmi-1 by miR-203 may play an important role in controlling cell proliferation and self-renewal of esophageal cancer stem-like cells. It may also promote the development of new therapeutic strategies and efficient drugs that target ESCC stem-like cells.

  4. An opposite effect of the CDK inhibitor, p18(INK4c) on embryonic stem cells compared with tumor and adult stem cells.

    PubMed

    Li, Yanxin; Pal, Rekha; Sung, Li-Ying; Feng, Haizhong; Miao, Weimin; Cheng, Shi-Yuan; Tian, Cindy; Cheng, Tao

    2012-01-01

    Self-renewal is a feature common to both adult and embryonic stem (ES) cells, as well as tumor stem cells (TSCs). The cyclin-dependent kinase inhibitor, p18(INK4c), is a known tumor suppressor that can inhibit self-renewal of tumor cells or adult stem cells. Here, we demonstrate an opposite effect of p18 on ES cells in comparison with teratoma cells. Our results unexpectedly showed that overexpression of p18 accelerated the growth of mouse ES cells and embryonic bodies (EB); on the contrary, inhibited the growth of late stage teratoma. Up-regulation of ES cell markers (i.e., Oct4, Nanog, Sox2, and Rex1) were detected in both ES and EB cells, while concomitant down-regulation of various differentiation markers was observed in EB cells. These results demonstrate that p18 has an opposite effect on ES cells as compared with tumor cells and adult stem cells. Mechanistically, expression of CDK4 was significantly increased with overexpression of p18 in ES cells, likely leading to a release of CDK2 from the inhibition by p21 and p27. As a result, self-renewal of ES cells was enhanced. Our current study suggests that targeting p18 in different cell types may yield different outcomes, thereby having implications for therapeutic manipulations of cell cycle machinery in stem cells. PMID:23049777

  5. Becoming a Blood Stem Cell Donor

    MedlinePlus

    ... total__ Find out why Close Becoming a Blood Stem Cell Donor NCIcancertopics Subscribe Subscribed Unsubscribe 359 359 Loading... ... Ever considered becoming a bone marrow or blood stem cell donor? Follow this true story of a former ...

  6. Stem Cell Transplant Patients and Fungal Infections

    MedlinePlus

    ... Foodborne, Waterborne, and Environmental Diseases Mycotic Diseases Branch Stem Cell Transplant Patients and Fungal Infections Recommend on Facebook ... Mold . Top of Page Preventing fungal infections in stem cell transplant patients Fungi are difficult to avoid because ...

  7. Adult Stem Cells and Diabetes Therapy

    PubMed Central

    Ilgun, Handenur; Kim, Joseph William; Luo, LuGuang

    2016-01-01

    The World Health Organization estimates that diabetes will be the fourth most prevalent disease by 2050. Developing a new therapy for diabetes is a challenge for researchers and clinicians in field. Many medications are being used for treatment of diabetes however with no conclusive and effective results therefore alternative therapies are required. Stem cell therapy is a promising tool for diabetes therapy, and it has involved embryonic stem cells, adult stem cells, and pluripotent stem cells. In this review, we focus on adult stem cells, especial human bone marrow stem cells (BM) for diabetes therapy, its history, and current development. We discuss prospects for future diabetes therapy such as induced pluripotent stem cells which have popularity in stem cell research area. PMID:27123495

  8. Stem cell technology for neurodegenerative diseases.

    PubMed

    Lunn, J Simon; Sakowski, Stacey A; Hur, Junguk; Feldman, Eva L

    2011-09-01

    Over the past 20 years, stem cell technologies have become an increasingly attractive option to investigate and treat neurodegenerative diseases. In the current review, we discuss the process of extending basic stem cell research into translational therapies for patients suffering from neurodegenerative diseases. We begin with a discussion of the burden of these diseases on society, emphasizing the need for increased attention toward advancing stem cell therapies. We then explain the various types of stem cells utilized in neurodegenerative disease research, and outline important issues to consider in the transition of stem cell therapy from bench to bedside. Finally, we detail the current progress regarding the applications of stem cell therapies to specific neurodegenerative diseases, focusing on Parkinson disease, Huntington disease, Alzheimer disease, amyotrophic lateral sclerosis, and spinal muscular atrophy. With a greater understanding of the capacity of stem cell technologies, there is growing public hope that stem cell therapies will continue to progress into realistic and efficacious treatments for neurodegenerative diseases.

  9. Perspectives on human stem cell research.

    PubMed

    Jung, Kyu Won

    2009-09-01

    Human stem cell research draws not only scientists' but the public's attention. Human stem cell research is considered to be able to identify the mechanism of human development and change the paradigm of medical practices. However, there are heated ethical and legal debates about human stem cell research. The core issue is that of human dignity and human life. Some prefer human adult stem cell research or iPS cell research, others hES cell research. We do not need to exclude any type of stem cell research because each has its own merits and issues, and they can facilitate the scientific revolution when working together.

  10. [Genetic regulation of plant shoot stem cells].

    PubMed

    Al'bert, E V; Ezhova, T A

    2013-02-01

    This article describes the main features of plant stem cells and summarizes the results of studies of the genetic control of stem cell maintenance in the apical meristem of the shoot. It is demonstrated that the WUS-CLV gene system plays a key role in the maintenance of shoot apical stem cells and the formation of adventitious buds and somatic embryos. Unconventional concepts of plant stem cells are considered.

  11. Stem Cell Research Policies around the World

    PubMed Central

    Dhar, Deepali; Hsi-en Ho, John

    2009-01-01

    The proliferation of stem cell research, conflated with its ethical and moral implications, has led governments to attempt regulation of both the science and funding of stem cells. Due to a diversity of opinions and cultural viewpoints, no single policy or set of rules exist to govern stem cell research. Instead, each country has developed its own policy. The following map catalogs the general legal and political milleu regarding stem cell research by country. PMID:19774124

  12. Sox10 Regulates Stem/Progenitor and Mesenchymal Cell States in Mammary Epithelial Cells.

    PubMed

    Dravis, Christopher; Spike, Benjamin T; Harrell, J Chuck; Johns, Claire; Trejo, Christy L; Southard-Smith, E Michelle; Perou, Charles M; Wahl, Geoffrey M

    2015-09-29

    To discover mechanisms that mediate plasticity in mammary cells, we characterized signaling networks that are present in the mammary stem cells responsible for fetal and adult mammary development. These analyses identified a signaling axis between FGF signaling and the transcription factor Sox10. Here, we show that Sox10 is specifically expressed in mammary cells exhibiting the highest levels of stem/progenitor activity. This includes fetal and adult mammary cells in vivo and mammary organoids in vitro. Sox10 is functionally relevant, as its deletion reduces stem/progenitor competence whereas its overexpression increases stem/progenitor activity. Intriguingly, we also show that Sox10 overexpression causes mammary cells to undergo a mesenchymal transition. Consistent with these findings, Sox10 is preferentially expressed in stem- and mesenchymal-like breast cancers. These results demonstrate a signaling mechanism through which stem and mesenchymal states are acquired in mammary cells and suggest therapeutic avenues in breast cancers for which targeted therapies are currently unavailable. PMID:26365194

  13. Stem cells and colorectal carcinogenesis

    PubMed Central

    Stoian, M; Stoica, V; Radulian, G

    2016-01-01

    Abstract Colorectal cancer represents an important cause of mortality and morbidity. Unfortunately, the physiopathology is still under study. There are theories about carcinogenesis and it is known that not only a single factor is responsible for the development of a tumor, but several conditions. Stem cells are a promising target for the treatment of colorectal cancer, along with the environment that has an important role. It has been postulated that mutations within the adult colonic stem cells may induce neoplastic changes. This theory is based on the observation that within a colon cancer, less than 1% of the neoplastic cells have the ability to regenerate the tumor and therefore they are responsible for recurrence. It is important to know that a new way of treatment needs to be found, since these cells are resistant to chemotherapy and radiotherapy.

  14. Stem/Progenitor cells in vascular regeneration.

    PubMed

    Zhang, Li; Xu, Qingbo

    2014-06-01

    A series of studies has been presented in the search for proof of circulating and resident vascular progenitor cells, which can differentiate into endothelial and smooth muscle cells and pericytes in animal and human studies. In terms of pluripotent stem cells, including embryonic stem cells, iPS, and partial-iPS cells, they display a great potential for vascular lineage differentiation. Development of stem cell therapy for treatment of vascular and ischemic diseases remains a major challenging research field. At the present, there is a clear expansion of research into mechanisms of stem cell differentiation into vascular lineages that are tested in animal models. Although there are several clinical trials ongoing that primarily focus on determining the benefits of stem cell transplantation in ischemic heart or peripheral ischemic tissues, intensive investigation for translational aspects of stem cell therapy would be needed. It is a hope that stem cell therapy for vascular diseases could be developed for clinic application in the future.

  15. College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning

    ERIC Educational Resources Information Center

    Concannon, James P.; Siegel, Marcelle A.; Halverson, Kristy; Freyermuth, Sharyn

    2010-01-01

    In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before…

  16. Setting FIRES to Stem Cell Research

    ERIC Educational Resources Information Center

    Miller, Roxanne Grietz

    2005-01-01

    The goal of this lesson is to present the basic scientific knowledge about stem cells, the promise of stem cell research to medicine, and the ethical considerations and arguments involved. One of the challenges of discussing stem cell research is that the field is constantly evolving and the most current information changes almost daily. Few…

  17. Blood-Forming Stem Cell Transplants

    MedlinePlus

    ... Health Professionals Questions to Ask about Your Treatment Research Blood-Forming Stem Cell Transplants On This Page What are bone marrow ... are evaluating BMT and PBSCT in clinical trials (research studies) for the treatment ... are the donor’s stem cells matched to the patient’s stem cells in allogeneic ...

  18. Extinction models for cancer stem cell therapy

    PubMed Central

    Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S.; Lange, Kenneth L.

    2012-01-01

    Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth–death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives

  19. 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.

  20. Induced Developmental Arrest of Early Hematopoietic Progenitors Leads to the Generation of Leukocyte Stem Cells

    PubMed Central

    Ikawa, Tomokatsu; Masuda, Kyoko; Huijskens, Mirelle J.A.J.; Satoh, Rumi; Kakugawa, Kiyokazu; Agata, Yasutoshi; Miyai, Tomohiro; Germeraad, Wilfred T.V.; Katsura, Yoshimoto; Kawamoto, Hiroshi

    2015-01-01

    Summary Self-renewal potential and multipotency are hallmarks of a stem cell. It is generally accepted that acquisition of such stemness requires rejuvenation of somatic cells through reprogramming of their genetic and epigenetic status. We show here that a simple block of cell differentiation is sufficient to induce and maintain stem cells. By overexpression of the transcriptional inhibitor ID3 in murine hematopoietic progenitor cells and cultivation under B cell induction conditions, the cells undergo developmental arrest and enter a self-renewal cycle. These cells can be maintained in vitro almost indefinitely, and the long-term cultured cells exhibit robust multi-lineage reconstitution when transferred into irradiated mice. These cells can be cloned and re-expanded with 50% plating efficiency, indicating that virtually all cells are self-renewing. Equivalent progenitors were produced from human cord blood stem cells, and these will ultimately be useful as a source of cells for immune cell therapy. PMID:26607950

  1. Modern stem cell therapy: approach to disease.

    PubMed

    Zemljic, Mateja; Pejkovic, Bozena; Krajnc, Ivan; Kocbek, Lidija

    2015-12-01

    Various types of stem cells exist, each with their own advantages and disadvantages. Considering the current available evidence, important preclinical and clinical studies regarding the therapeutic potential of stem cells, stem cell therapy might be the important strategy for tissue repair. The development of stem cell therapy for tissue repair has primarily relied on stem cells, especially mesenchymal stem cells. Multilineage differentiation into all of the described cells are considered as important candidates for a range of diseases like neurological diseases, cardiovascular diseases, gastrointestinal cancer and genetic defects, as well as for acute and chronic wounds healing and pharmaceutical treatment. We review the properties and multipotency of stem cells and their differentiation potential, once cultured under specific growth conditions, for use in cell-based therapies and functional tissue replacement.

  2. Nuclear Mechanics and Stem Cell Differentiation.

    PubMed

    Mao, Xinjian; Gavara, Nuria; Song, Guanbin

    2015-12-01

    Stem cells are characterized by their self-renewal and multi-lineage differentiation potential. Stem cell differentiation is a prerequisite for the application of stem cells in regenerative medicine and clinical therapy. In addition to chemical stimulation, mechanical cues play a significant role in regulating stem cell differentiation. The integrity of mechanical sensors is necessary for the ability of cells to respond to mechanical signals. The nucleus, the largest and stiffest cellular organelle, interacts with the cytoskeleton as a key mediator of cell mechanics. Nuclear mechanics are involved in the complicated interactions of lamins, chromatin and nucleoskeleton-related proteins. Thus, stem cell differentiation is intimately associated with nuclear mechanics due to its indispensable role in mechanotransduction and mechanical response. This paper reviews several main contributions of nuclear mechanics, highlights the hallmarks of the nuclear mechanics of stem cells, and provides insight into the relationship between nuclear mechanics and stem cell differentiation, which may guide clinical applications in the future.

  3. Stem cells: science, policy, and ethics.

    PubMed

    Fischbach, Gerald D; Fischbach, Ruth L

    2004-11-01

    Human embryonic stem cells offer the promise of a new regenerative medicine in which damaged adult cells can be replaced with new cells. Research is needed to determine the most viable stem cell lines and reliable ways to promote the differentiation of pluripotent stem cells into specific cell types (neurons, muscle cells, etc). To create new cell lines, it is necessary to destroy preimplantation blastocysts. This has led to an intense debate that threatens to limit embryonic stem cell research. The profound ethical issues raised call for informed, dispassionate debate.

  4. Can Nanomedicines Kill Cancer Stem Cells?

    PubMed Central

    Zhao, Yi; Alakhova, Daria Y.; Kabanov, Alexander V.

    2014-01-01

    Most tumors are heterogeneous and many cancers contain small population of highly tumorigenic and intrinsically drug resistant cancer stem cells (CSCs). Like normal stem cell, CSCs have ability to self-renew and differentiate to other tumor cell types. They are believed to be a source for drug resistance, tumor recurrence and metastasis. CSCs often overexpress drug efflux transporters, spend most of their time in non-dividing G0 cell cycle state, and therefore, can escape the conventional chemotherapies. Thus, targeting CSCs is essential for developing novel therapies to prevent cancer relapse and emerging of drug resistance. Nanocarrier-based therapeutic agents (nanomedicines) have been used to achieve longer circulation times, better stability and bioavailability over current therapeutics. Recently, some groups have successfully applied nanomedicines to target CSCs to eliminate the tumor and prevent its recurrence. These approaches include 1) delivery of therapeutic agents (small molecules, siRNA, antibodies) that affect embryonic signaling pathways implicated in self-renewal and differentiation in CSCs, 2) inhibiting drug efflux transporters in an attempt to sensitize CSCs to therapy, 3) targeting metabolism in CSCs through nanoformulated chemicals and field-responsive magnetic nanoparticles and carbon nanotubes, and 4) disruption of multiple pathways in drug resistant cells using combination of chemotherapeutic drugs with amphiphilic Pluronic block copolymers. Despite clear progress of these studies the challenges of targeting CSCs by nanomedicines still exist and leave plenty of room for improvement and development. This review summarizes biological processes that are related to CSCs, overviews the current state of anti-CSCs therapies, and discusses state-of-the-art nanomedicine approaches developed to kill CSCs. PMID:24120657

  5. Muscle stem cells at a glance

    PubMed Central

    Wang, Yu Xin; Dumont, Nicolas A.; Rudnicki, Michael A.

    2014-01-01

    ABSTRACT Muscle stem cells facilitate the long-term regenerative capacity of skeletal muscle. This self-renewing population of satellite cells has only recently been defined through genetic and transplantation experiments. Although muscle stem cells remain in a dormant quiescent state in uninjured muscle, they are poised to activate and produce committed progeny. Unlike committed myogenic progenitor cells, the self-renewal capacity gives muscle stem cells the ability to engraft as satellite cells and capitulate long-term regeneration. Similar to other adult stem cells, understanding the molecular regulation of muscle stem cells has significant implications towards the development of pharmacological or cell-based therapies for muscle disorders. This Cell Science at a Glance article and accompanying poster will review satellite cell characteristics and therapeutic potential, and provide an overview of the muscle stem cell hallmarks: quiescence, self-renewal and commitment. PMID:25300792

  6. Cell motion predicts human epidermal stemness

    PubMed Central

    Toki, Fujio; Tate, Sota; Imai, Matome; Matsushita, Natsuki; Shiraishi, Ken; Sayama, Koji; Toki, Hiroshi; Higashiyama, Shigeki

    2015-01-01

    Image-based identification of cultured stem cells and noninvasive evaluation of their proliferative capacity advance cell therapy and stem cell research. Here we demonstrate that human keratinocyte stem cells can be identified in situ by analyzing cell motion during their cultivation. Modeling experiments suggested that the clonal type of cultured human clonogenic keratinocytes can be efficiently determined by analysis of early cell movement. Image analysis experiments demonstrated that keratinocyte stem cells indeed display a unique rotational movement that can be identified as early as the two-cell stage colony. We also demonstrate that α6 integrin is required for both rotational and collective cell motion. Our experiments provide, for the first time, strong evidence that cell motion and epidermal stemness are linked. We conclude that early identification of human keratinocyte stem cells by image analysis of cell movement is a valid parameter for quality control of cultured keratinocytes for transplantation. PMID:25897083

  7. Hypoxia-Regulated Delta-like 1 Homologue Enhances Cancer Cell Stemness and Tumorigenicity

    PubMed Central

    Kim, Yuri; Lin, Qun; Zelterman, Daniel; Yun, Zhong

    2010-01-01

    Reduced oxygenation, or hypoxia, inhibits differentiation and facilitates stem cell maintenance. Hypoxia commonly occurs in solid tumors and promotes malignant progression. Hypoxic tumors are aggressive and exhibit stem cell–like characteristics. It remains unclear, however, whether and how hypoxia regulates cancer cell differentiation and maintains cancer cell stemness. Here, we show that hypoxia increases the expression of the stem cell gene DLK1, or delta-like 1 homologue (Drosophila), in neuronal tumor cells. Inhibition of DLK1 enhances spontaneous differentiation, decreases clonogenicity, and reduces in vivo tumor growth. Overexpression of DLK1 inhibits differentiation and enhances tumorigenic potentials. We further show that the DLK1 cytoplasmic domain, especially Tyrosine339 and Serine355, is required for maintaining both clonogenicity and tumorigenicity. Because elevated DLK1 expression is found in many tumor types, our observations suggest that hypoxia and DLK1 may constitute an important stem cell pathway for the regulation of cancer stem cell–like functionality and tumorigenicity. PMID:19934310

  8. Cholesteatoma Fibroblasts Promote Epithelial Cell Proliferation through Overexpression of Epiregulin

    PubMed Central

    Yoshikawa, Mamoru; Kojima, Hiromi; Yaguchi, Yuichiro; Okada, Naoko; Saito, Hirohisa; Moriyama, Hiroshi

    2013-01-01

    To investigate whether keratinocytes proliferate in response to epiregulin produced by subepithelial fibroblasts derived from middle ear cholesteatoma. Tissue samples were obtained from patients undergoing tympanoplasty. The quantitative polymerase chain reaction and immunohistochemistry were performed to examine epiregulin expression and localization in cholesteatoma tissues and retroauricular skin tissues. Fibroblasts were cultured from cholesteatoma tissues and from normal retroauricular skin. These fibroblasts were used as feeder cells for culture with a human keratinocyte cell line (PHK16-0b). To investigate the role of epiregulin in colony formation by PHK16-0b cells, epiregulin mRNA expression was knocked down in fibroblasts by using short interfering RNA and epiregulin protein was blocked with a neutralizing antibody. Epiregulin mRNA expression was significantly elevated in cholesteatoma tissues compared with that in normal retroauricular skin. Staining for epiregulin was more intense in the epithelial cells and subepithelial fibroblasts of cholesteatoma tissues than in retroauricular skin. When PHK16-0b cells were cultured with cholesteatoma fibroblasts, their colony-forming efficiency was 50% higher than when these cells were cultured with normal skin fibroblasts. Also, knockdown of epiregulin mRNA in cholesteatoma fibroblasts led to greater suppression of colony formation than knockdown in skin fibroblasts. Furthermore, the colony-forming efficiency of PHK16-0b cells was significantly reduced after treatment with an epiregulin neutralizing antibody in co-culture with cholesteatoma fibroblasts, but not in co-culture with skin fibroblasts. These results suggest that keratinocyte hyperproliferation in cholesteatoma is promoted through overexpression of epiregulin by subepithelial fibroblasts via epithelial–mesenchymal interactions, which may play a crucial role in the pathogenesis of middle ear cholesteatoma. PMID:23826119

  9. Embryonic Stem Cell Patents and Human Dignity

    PubMed Central

    Resnik, David B.

    2009-01-01

    This article examines the assertion that human embryonic stem cells patents are immoral because they violate human dignity. After analyzing the concept of human dignity and its role in bioethics debates, this article argues that patents on human embryos or totipotent embryonic stem cells violate human dignity, but that patents on pluripotent or multipotent stem cells do not. Since patents on pluripotent or multipotent stem cells may still threaten human dignity by encouraging people to treat embryos as property, patent agencies should carefully monitor and control these patents to ensure that patents are not inadvertently awarded on embryos or totipotent stem cells. PMID:17922198

  10. Stem cell maintenance in a different niche

    PubMed Central

    Ahn, Ji Yeon; Lee, Seung Tae

    2013-01-01

    To overcome the difficulty of controlling stem cell fate and function in applications to regenerative medicine, a number of alternative approaches have been made. Recent reports demonstrate that a non-cellular niche modulating the biophysical microenvironment with chemical factors can support stem cell self-renewal. In our previous studies, early establishment was executed to optimize biophysical factors and it was subsequently found that the microgeometry of the extracellular matrix made huge differences in stem cell behavior and phenotype. We review here a three-dimensional, non-cellular niche designed to support stem cell self-renewal. The characteristics of stem cells under the designed system are further discussed. PMID:23875159

  11. Galectin-1 is overexpressed in CD133+ human lung adenocarcinoma cells and promotes their growth and invasiveness

    PubMed Central

    Zhou, Xuefeng; Li, Dan; Wang, Xianguo; Zhang, Bo; Zhu, Hua; Zhao, Jinping

    2015-01-01

    Previous studies demonstrated that a subpopulation of cancer cells, which are CD133 positive (CD133+) feature higher invasive and metastatic abilities, are called cancer stem cells (CSCs). By using tumor cells derived from patients with lung adenocarcinoma, we found that galectin-1 is highly overexpressed in the CD133+ cancer cells as compared to the normal cancer cells (CD133−) from the same patients. We overexpressed galectin-1 in CD133− cancer cells and downregulated it in CSCs. We found that overexpression of galectin-1 promoted invasiveness of CD133− cells, while knockdown of galectin-1 suppressed proliferation, colony formation and invasiveness of CSCs. Furthermore, tumor growth was significantly inhibited in CSCs xenografts with knockdown of galectin-1 as compared to CSCs treated with scramble siRNAs. Biochemical studies revealed that galectin-1 knockdown led to the suppression of COX-2/PGE2 and AKT/mTOR pathways, indicating galectin-1 might control the phenotypes of CSCs by regulating these signaling pathways. Finally, a retrospective study revealed that galectin-1 levels in blood circulation negatively correlates with overall survival and positively correlates with lymph node metastasis of the patients. Taken together, these findings suggested that galectin-1 plays a major role on the tumorigenesis and invasiveness of CD133+ cancer cells and might serve as a potential therapeutic target for treatment of human patients with lung adenocarcinoma. PMID:25605013

  12. 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.

  13. Plasticity of hematopoietic stem cells.

    PubMed

    Ogawa, Makio; LaRue, Amanda C; Mehrotra, Meenal

    2015-01-01

    Almost two decades ago, a number of cell culture and preclinical transplantation studies suggested the striking concept of the tissue-reconstituting ability of hematopoietic stem cells (HSCs). While this heralded an exciting time of radically new therapies for disorders of many organs and tissues, the concept was soon mired by controversy and remained dormant. This chapter provides a brief review of evidence for HSC plasticity including our findings based on single HSC transplantation in mouse. These studies strongly support the concept that HSCs are pluripotent and may be the source for the majority, if not all, of the cell types in our body. PMID:26590762

  14. Klotho, stem cells, and aging

    PubMed Central

    Bian, Ao; Neyra, Javier A; Zhan, Ming; Hu, Ming Chang

    2015-01-01

    Aging is an inevitable and progressive biological process involving dysfunction and eventually destruction of every tissue and organ. This process is driven by a tightly regulated and complex interplay between genetic and acquired factors. Klotho is an antiaging gene encoding a single-pass transmembrane protein, klotho, which serves as an aging suppressor through a wide variety of mechanisms, such as antioxidation, antisenescence, antiautophagy, and modulation of many signaling pathways, including insulin-like growth factor and Wnt. Klotho deficiency activates Wnt expression and activity contributing to senescence and depletion of stem cells, which consequently triggers tissue atrophy and fibrosis. In contrast, the klotho protein was shown to suppress Wnt-signaling transduction, and inhibit cell senescence and preserve stem cells. A better understanding of the potential effects of klotho on stem cells could offer novel insights into the cellular and molecular mechanisms of klotho deficiency-related aging and disease. The klotho protein may be a promising therapeutic agent for aging and aging-related disorders. PMID:26346243

  15. Klotho, stem cells, and aging.

    PubMed

    Bian, Ao; Neyra, Javier A; Zhan, Ming; Hu, Ming Chang

    2015-01-01

    Aging is an inevitable and progressive biological process involving dysfunction and eventually destruction of every tissue and organ. This process is driven by a tightly regulated and complex interplay between genetic and acquired factors. Klotho is an antiaging gene encoding a single-pass transmembrane protein, klotho, which serves as an aging suppressor through a wide variety of mechanisms, such as antioxidation, antisenescence, antiautophagy, and modulation of many signaling pathways, including insulin-like growth factor and Wnt. Klotho deficiency activates Wnt expression and activity contributing to senescence and depletion of stem cells, which consequently triggers tissue atrophy and fibrosis. In contrast, the klotho protein was shown to suppress Wnt-signaling transduction, and inhibit cell senescence and preserve stem cells. A better understanding of the potential effects of klotho on stem cells could offer novel insights into the cellular and molecular mechanisms of klotho deficiency-related aging and disease. The klotho protein may be a promising therapeutic agent for aging and aging-related disorders. PMID:26346243

  16. Klotho, stem cells, and aging.

    PubMed

    Bian, Ao; Neyra, Javier A; Zhan, Ming; Hu, Ming Chang

    2015-01-01

    Aging is an inevitable and progressive biological process involving dysfunction and eventually destruction of every tissue and organ. This process is driven by a tightly regulated and complex interplay between genetic and acquired factors. Klotho is an antiaging gene encoding a single-pass transmembrane protein, klotho, which serves as an aging suppressor through a wide variety of mechanisms, such as antioxidation, antisenescence, antiautophagy, and modulation of many signaling pathways, including insulin-like growth factor and Wnt. Klotho deficiency activates Wnt expression and activity contributing to senescence and depletion of stem cells, which consequently triggers tissue atrophy and fibrosis. In contrast, the klotho protein was shown to suppress Wnt-signaling transduction, and inhibit cell senescence and preserve stem cells. A better understanding of the potential effects of klotho on stem cells could offer novel insights into the cellular and molecular mechanisms of klotho deficiency-related aging and disease. The klotho protein may be a promising therapeutic agent for aging and aging-related disorders.

  17. Combination Cell Therapy with Mesenchymal Stem Cells and Neural Stem Cells for Brain Stroke in Rats

    PubMed Central

    Hosseini, Seyed Mojtaba; Farahmandnia, Mohammad; Razi, Zahra; Delavari, Somayeh; Shakibajahromi, Benafsheh; Sarvestani, Fatemeh Sabet; Kazemi, Sepehr; Semsar, Maryam

    2015-01-01

    Objectives Brain stroke is the second most important events that lead to disability and morbidity these days. Although, stroke is important, there is no treatment for curing this problem. Nowadays, cell therapy has opened a new window for treating central nervous system disease. In some previous studies the Mesenchymal stem cells and neural stem cells. In this study, we have designed an experiment to assess the combination cell therapy (Mesenchymal and Neural stem cells) effects on brain stroke. Method and Materials The Mesenchymal stem cells were isolated from adult rat bone marrow and the neural stem cells were isolated from ganglion eminence of rat embryo 14 days. The Mesenchymal stem cells were injected 1 day after middle cerebral artery occlusion (MCAO) and the neural stem cells transplanted 7 day after MCAO. After 28 days, the neurological outcomes and brain lesion volumes were evaluated. Also, the activity of Caspase 3 was assessed in different groups. Result The group which received combination cell therapy had better neurological examination and less brain lesion. Also the combination cell therapy group had the least Caspase 3 activity among the groups. Conclusions The combination cell therapy is more effective than Mesenchymal stem cell therapy and neural stem cell therapy separately in treating the brain stroke in rats. PMID:26019759

  18. Overexpression of membrane proteins in mammalian cells for structural studies

    PubMed Central

    Andréll, Juni

    2013-01-01

    The number of structures of integral membrane proteins from higher eukaryotes is steadily increasing due to a number of innovative protein engineering and crystallization strategies devised over the last few years. However, it is sobering to reflect that these structures represent only a tiny proportion of the total number of membrane proteins encoded by a mammalian genome. In addition, the structures determined to date are of the most tractable membrane proteins, i.e., those that are expressed functionally and to high levels in yeast or in insect cells using the baculovirus expression system. However, some membrane proteins that are expressed inefficiently in these systems can be produced at sufficiently high levels in mammalian cells to allow structure determination. Mammalian expression systems are an under-used resource in structural biology and represent an effective way to produce fully functional membrane proteins for structural studies. This review will discuss examples of vertebrate membrane protein overexpression in mammalian cells using a variety of viral, constitutive or inducible expression systems. PMID:22963530

  19. Stem Cells News Update: A Personal Perspective

    PubMed Central

    Wong, SC

    2013-01-01

    This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy. PMID:24778557

  20. [Stem cells and tissue engineering techniques].

    PubMed

    Sica, Gigliola

    2013-01-01

    The therapeutic use of stem cells and tissue engineering techniques are emerging in urology. Here, stem cell types, their differentiating potential and fundamental characteristics are illustrated. The cancer stem cell hypothesis is reported with reference to the role played by stem cells in the origin, development and progression of neoplastic lesions. In addition, recent reports of results obtained with stem cells alone or seeded in scaffolds to overcome problems of damaged urinary tract tissue are summarized. Among others, the application of these biotechnologies in urinary bladder, and urethra are delineated. Nevertheless, apart from the ethical concerns raised from the use of embryonic stem cells, a lot of questions need to be solved concerning the biology of stem cells before their widespread use in clinical trials. Further investigation is also required in tissue engineering utilizing animal models.

  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.

  2. Stem cells news update: a personal perspective.

    PubMed

    Wong, Sc

    2013-12-01

    This article is a follow-up to a previous Commentary published in 2011. It updates some of the events mentioned in that Commentary and continues with more interesting and exciting news on stem cell research and the emerging field of Regenerative Medicine. Some of the news includes: 1) the 2012 Nobel Prize for Medicine awarded to John B. Gurdon and Shinya Yamanaka; 2) the cloning of human embryonic stem cells; 3) the continued search for truly pluripotent adult stem cells via in vitro and in vivo protocols; 4) the breakthrough in organ replacements; 5) the global stem cell race; 6) the global stem cell cryo-preservation business; 7) the worldwide stem cell donor registries, and 8) the issue of government regulation on stem cell therapy.

  3. Stem cells and repair of lung injuries

    PubMed Central

    Neuringer, Isabel P; Randell, Scott H

    2004-01-01

    Fueled by the promise of regenerative medicine, currently there is unprecedented interest in stem cells. Furthermore, there have been revolutionary, but somewhat controversial, advances in our understanding of stem cell biology. Stem cells likely play key roles in the repair of diverse lung injuries. However, due to very low rates of cellular proliferation in vivo in the normal steady state, cellular and architectural complexity of the respiratory tract, and the lack of an intensive research effort, lung stem cells remain poorly understood compared to those in other major organ systems. In the present review, we concisely explore the conceptual framework of stem cell biology and recent advances pertinent to the lungs. We illustrate lung diseases in which manipulation of stem cells may be physiologically significant and highlight the challenges facing stem cell-related therapy in the lung. PMID:15285789

  4. 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

  5. Stem Cells, Science, and Public Reasoning

    ERIC Educational Resources Information Center

    Hurlbut, J. Benjamin; Robert, Jason Scott

    2012-01-01

    These are interesting days in the scientific, social, and political debates about human embryonic stem cell research. Pluripotent stem cells--cells that can, in principle, give rise to the body's full range of cell types--were previously derivable only from human embryos that were destroyed in the process. Now, a variety of somatic cell types can…

  6. Cancer Stem Cells Converted from Pluripotent Stem Cells and the Cancerous Niche

    PubMed Central

    Kasai, T; Chen, L; Mizutani, AZ; Kudoh, T; Murakami, H; Fu, L; Seno, M

    2014-01-01

    Nowadays, the cancer stem cells are considered to be significantly responsible for growth, metastasis, invasion and recurrence of all cancer. Cancer stem cells are typically characterized by continuous proliferation and self-renewal as well as by differentiation potential, while stem cells are considered to differentiate into tissue- specific phenotype of mature cells under the influence of micro-environment. Cancer stem cells should be traced to the stem cells under the influence of a micro-environment, which induces malignant tumors. In this review, we propose this micro-environment as a ‘cancerous niche’ and discuss its importance on the formation and maintenance of cancer stem cells with the recent experimental results to establish cancer stem cell models from induced pluripotent stem cells. These models of cancer stem cell will provide the great advantages in cancer research and its therapeutic applications in the future. PMID:25075155

  7. Learning about Cancer by Studying Stem Cells

    MedlinePlus

    ... About Cancer by Studying Stem Cells Inside Life Science View All Articles | Inside Life Science Home Page Learning About Cancer by Studying Stem ... Once Upon a Stem Cell This Inside Life Science article also appears on LiveScience . Learn about related ...

  8. Stem cells shine in Shanghai.

    PubMed

    Cheng, Linzhao; Xiao, Lei; Zeng, Fanyi; Zhang, Y Alex

    2008-01-10

    From November 6 to 9, 2007, more than 500 scientists from 20 countries and regions gathered in Shanghai, China, to attend the 2007 Shanghai International Symposium on Stem Cell Research. This dynamic meeting was jointly organized by the International Society for Stem Cell Research (ISSCR), the Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences (SIBS/CAS), and other institutes in China. For the first time, the ISSCR added its name to a conference other than its own annual meeting, embracing this opportunity to learn more about research that is happening in China and providing a platform for local researchers who do not always have the opportunity to travel internationally to the ISSCR annual meetings. Here we present a sampling of the diverse research presented by the local and international participants during the science-packed 4 day meeting.

  9. Adult stem cells and tissue repair.

    PubMed

    Körbling, M; Estrov, Z; Champlin, R

    2003-08-01

    Recently, adult stem cells originating from bone marrow or peripheral blood have been suggested to contribute to repair and genesis of cells specific for liver, cardiac and skeletal muscle, gut, and brain tissue. The mechanism involved has been termed transdifferentiation, although other explanations including cell fusion have been postulated. Using adult stem cells to generate or repair solid organ tissue obviates the immunologic, ethical, and teratogenic issues that accompany embryonic stem cells.

  10. Cancer stem cells and metastasis.

    PubMed

    Sampieri, Katia; Fodde, Riccardo

    2012-06-01

    Cancer stem cells (CSCs) represent a subpopulation of tumour cells endowed with self-renewal and multi-lineage differentiation capacity but also with an innate resistance to cytotoxic agents, a feature likely to pose major clinical challenges towards the complete eradication of minimal residual disease in cancer patients. Operationally, CSCs are defined by their tumour-propagating ability when serially transplanted into immune-compromised mice and by their capacity to fully recapitulate the original heterogeneity of cell types observed in the primary lesions they are derived from. CSCs were first identified in haematopoietic malignancies and later in a broad spectrum of solid tumours including those of the breast, colon and brain. Notably, several CSC characteristics are relevant to metastasis, such as motility, invasiveness and, as mentioned above, resistance to DNA damage-induced apoptosis. Here, we have reviewed the current literature on the relation between CSCs and metastasis formation. Preliminary studies on cancer cell lines and patient-derived material suggest a rate-limiting role for stem-like cells in the processes of tumour cell dissemination and metastasis formation. However, additional studies are needed to deliver formal proof of their identity as the cell of origin of recurrences at distant organ sites. Nevertheless, several studies have already provided pre-clinical evidence of the efficacy of novel therapies directed against disseminated CSCs.

  11. Generalized Potential of Adult Neural Stem Cells

    NASA Astrophysics Data System (ADS)

    Clarke, Diana L.; Johansson, Clas B.; Wilbertz, Johannes; Veress, Biborka; Nilsson, Erik; Karlström, Helena; Lendahl, Urban; Frisén, Jonas

    2000-06-01

    The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation of chimeric chick and mouse embryos and give rise to cells of all germ layers. This demonstrates that an adult neural stem cell has a very broad developmental capacity and may potentially be used to generate a variety of cell types for transplantation in different diseases.

  12. Mesenchymal Stem Cells in Hematopoietic Stem Cell Transplantation

    PubMed Central

    Battiwalla, Minoo; Hematti, Peiman

    2009-01-01

    Mesenchymal stromal/stem cells (MSCs) of bone marrow (BM) origin not only provide the supportive microenvironmental niche for hematopoietic stem cells (HSCs) but are also capable of differentiating into various cell types of mesenchymal origin, such as bone, fat, and cartilage. In vitro and in vivo data suggest that MSCs have low inherent immunogenicity, modulate/suppress immunological responses through interactions with immune cells, and home to damaged tissues to participate in regeneration processes through their diverse biological properties. MSCs derived from BM are being evaluated for a wide range of clinical applications including disorders as diverse as myocardial infarction or newly diagnosed diabetes mellitus type-1. However, their use in HSC transplantation, either for enhancement of hematopoietic engraftment or for treatment/prevention of graft versus host disease, is far ahead of other indications. Ease of isolation and ex vivo expansion of MSCs, combined with their intriguing immunomodulatory properties, and their impressive record of safety in a wide variety of clinical trials make these cells promising candidates for further investigation. PMID:19728189

  13. CANCER STEM CELLS AND RADIORESISTANCE

    PubMed Central

    K, Rycaj; D.G, Tang

    2015-01-01

    Purpose Radiation therapy has made significant contributions to cancer therapy. However, despite continuous improvements, tumor recurrence and therapy resistance still occur in a high proportion of patients. One underlying reason for this radioresistance might be attributable to the presence of cancer stem cells (CSCs). Conclusions This review discusses CSC-specific mechanisms that confer radiation resistance with a focus on breast cancer and glioblastoma multiforme (GBM), thereby emphasizing the addition of these potential therapeutic targets in order to potentiate radiotherapy efficacy. PMID:24527669

  14. Stem cells - biological update and cell therapy progress.

    PubMed

    Girlovanu, Mihai; Susman, Sergiu; Soritau, Olga; Rus-Ciuca, Dan; Melincovici, Carmen; Constantin, Anne-Marie; Mihu, Carmen Mihaela

    2015-01-01

    In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods to prevent teratoma formation or the ethical and religious issues regarding especially the embryonic stem cell research. The direct differentiation of stem cells into specialized cells: cardiac myocytes, neural cells, pancreatic islets cells, may represent an option in treating incurable diseases such as: neurodegenerative diseases, type I diabetes, hematologic or cardiac diseases. Nevertheless, stem cell-based therapies, based on stem cell transplantation, remain mainly at the experimental stages and their major limitation is the development of teratoma and cancer after transplantation. The induced pluripotent stem cells (hiPSCs) represent a prime candidate for future cell therapy research because of their significant self-renewal and differentiation potential and the lack of ethical issues. This article presents an overview of the biological advances in the study of stem cells and the current progress made in the field of regenerative medicine.

  15. Stem cell tracking with optically active nanoparticles

    PubMed Central

    Gao, Yu; Cui, Yan; Chan, Jerry KY; Xu, Chenjie

    2013-01-01

    Stem-cell-based therapies hold promise and potential to address many unmet clinical needs. Cell tracking with modern imaging modalities offers insight into the underlying biological process of the stem-cell-based therapies, with the goal to reveal cell survival, migration, homing, engraftment, differentiation, and functions. Adaptability, sensitivity, resolution, and non-invasiveness have contributed to the longstanding use of optical imaging for stem cell tracking and analysis. To identify transplanted stem cells from the host tissue, optically active probes are usually used to label stem cells before the administration. In comparison to the traditional fluorescent probes like fluorescent proteins and dyes, nanoparticle-based probes are advantageous in terms of the photo-stabilities and minimal changes to the cell phenotype. The main focus here is to overview the recent development of optically active nanoparticles for stem cells tracking. The related optical imaging modalities include fluorescence imaging, photoacoustic imaging, Raman and surface enhanced Raman spectroscopy imaging. PMID:23638335

  16. DAPIT Over-Expression Modulates Glucose Metabolism and Cell Behaviour in HEK293T Cells

    PubMed Central

    Kontro, Heidi; Cannino, Giuseppe; Rustin, Pierre; Dufour, Eric; Kainulainen, Heikki

    2015-01-01

    Introduction Diabetes Associated Protein in Insulin-sensitive Tissues (DAPIT) is a subunit of mitochondrial ATP synthase and has also been found to associate with the vacuolar H+-ATPase. Its expression is particularly high in cells with elevated aerobic metabolism and in epithelial cells that actively transport nutrients and ions. Deletion of DAPIT is known to induce loss of mitochondrial ATP synthase but the effects of its over-expression are obscure. Results In order to study the consequences of high expression of DAPIT, we constructed a transgenic cell line that constitutively expressed DAPIT in human embryonal kidney cells, HEK293T. Enhanced DAPIT expression decreased mtDNA content and mitochondrial mass, and saturated respiratory chain by decreasing H+-ATP synthase activity. DAPIT over-expression also increased mitochondrial membrane potential and superoxide level, and translocated the transcription factors hypoxia inducible factor 1α (Hif1α) and β-catenin to the nucleus. Accordingly, cells over-expressing DAPIT used more glucose and generated a larger amount of lactate compared to control cells. Interestingly, these changes were associated with an epithelial to mesenchymal (EMT)-like transition by changing E-cadherin to N-cadherin and up-regulating several key junction/adhesion proteins. At physiological level, DAPIT over-expression slowed down cell growth by G1 arrest and migration, and enhanced cell detachment. Several cancers also showed an increase in genomic copy number of Usmg5 (gene encoding DAPIT), thereby providing strong correlative evidence for DAPIT possibly having oncogenic function in cancers. Conclusions DAPIT over-expression thus appears to modulate mitochondrial functions and alter cellular regulations, promote anaerobic metabolism and induce EMT-like transition. We propose that DAPIT over-expression couples the changes in mitochondrial metabolism to physiological and pathophysiological regulations, and suggest it could play a critical

  17. Overexpression of LOXIN Protects Endothelial Progenitor Cells From Apoptosis Induced by Oxidized Low Density Lipoprotein.

    PubMed

    Veas, Carlos; Jara, Casandra; Willis, Naomi D; Pérez-Contreras, Karen; Gutierrez, Nicolas; Toledo, Jorge; Fernandez, Paulina; Radojkovic, Claudia; Zuñiga, Felipe A; Escudero, Carlos; Aguayo, Claudio

    2016-04-01

    Human endothelial progenitor cells (hEPC) are adult stem cells located in the bone marrow and peripheral blood. Studies have indicated that hEPC play an important role in the recovery and repair of injured endothelium, however, their quantity and functional capacity is reduced in several diseases including hypercholesterolemia. Recently, it has been demonstrated that hEPC express lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and its activation by oxidized low-density lipoprotein (ox-LDL) induces cellular dysfunction and apoptosis. This study aimed to investigate whether overexpression of LOXIN, a truncated isoform of LOX-1 that acts as a dominant negative, plays a protective role against ox-LDL-induced apoptosis in hEPC. Human endothelial progenitor cells exposed to ox-LDL showed a significant increase in LOX-1 expression, and apoptosis began at ox-LDL concentrations above 50 μg/mL. All hEPC apoptosed at 200 μg/mL ox-LDL. High LOXIN expression was generated using adenoviral systems in hEPC and SiHa cells transduced with 100 colony-forming units per cell. Transduced LOXIN localized to the plasma membrane and blocked ox-LDL uptake mediated by LOX-1. Overexpression of LOXIN protected hEPC from ox-LDL-induced apoptosis, and therefore maybe a novel way of improving hEPC function and quantity. These results suggest that adenoviral vectors of LOXIN may provide a possible treatment for diseases related to ox-LDL and vascular endothelium dysfunction, including atherosclerosis.

  18. Overexpression of LOXIN Protects Endothelial Progenitor Cells From Apoptosis Induced by Oxidized Low Density Lipoprotein.

    PubMed

    Veas, Carlos; Jara, Casandra; Willis, Naomi D; Pérez-Contreras, Karen; Gutierrez, Nicolas; Toledo, Jorge; Fernandez, Paulina; Radojkovic, Claudia; Zuñiga, Felipe A; Escudero, Carlos; Aguayo, Claudio

    2016-04-01

    Human endothelial progenitor cells (hEPC) are adult stem cells located in the bone marrow and peripheral blood. Studies have indicated that hEPC play an important role in the recovery and repair of injured endothelium, however, their quantity and functional capacity is reduced in several diseases including hypercholesterolemia. Recently, it has been demonstrated that hEPC express lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and its activation by oxidized low-density lipoprotein (ox-LDL) induces cellular dysfunction and apoptosis. This study aimed to investigate whether overexpression of LOXIN, a truncated isoform of LOX-1 that acts as a dominant negative, plays a protective role against ox-LDL-induced apoptosis in hEPC. Human endothelial progenitor cells exposed to ox-LDL showed a significant increase in LOX-1 expression, and apoptosis began at ox-LDL concentrations above 50 μg/mL. All hEPC apoptosed at 200 μg/mL ox-LDL. High LOXIN expression was generated using adenoviral systems in hEPC and SiHa cells transduced with 100 colony-forming units per cell. Transduced LOXIN localized to the plasma membrane and blocked ox-LDL uptake mediated by LOX-1. Overexpression of LOXIN protected hEPC from ox-LDL-induced apoptosis, and therefore maybe a novel way of improving hEPC function and quantity. These results suggest that adenoviral vectors of LOXIN may provide a possible treatment for diseases related to ox-LDL and vascular endothelium dysfunction, including atherosclerosis. PMID:26771151

  19. Stem cells in the nervous system.

    PubMed

    Maldonado-Soto, Angel R; Oakley, Derek H; Wichterle, Hynek; Stein, Joel; Doetsch, Fiona K; Henderson, Christopher E

    2014-11-01

    Given their capacity to regenerate cells lost through injury or disease, stem cells offer new vistas into possible treatments for degenerative diseases and their underlying causes. As such, stem cell biology is emerging as a driving force behind many studies in regenerative medicine. This review focuses on the current understanding of the applications of stem cells in treating ailments of the human brain, with an emphasis on neurodegenerative diseases. Two types of neural stem cells are discussed: endogenous neural stem cells residing within the adult brain and pluripotent stem cells capable of forming neural cells in culture. Endogenous neural stem cells give rise to neurons throughout life, but they are restricted to specialized regions in the brain. Elucidating the molecular mechanisms regulating these cells is key in determining their therapeutic potential as well as finding mechanisms to activate dormant stem cells outside these specialized microdomains. In parallel, patient-derived stem cells can be used to generate neural cells in culture, providing new tools for disease modeling, drug testing, and cell-based therapies. Turning these technologies into viable treatments will require the integration of basic science with clinical skills in rehabilitation.

  20. Stem Cells in the Nervous System

    PubMed Central

    Maldonado-Soto, Angel R.; Oakley, Derek H.; Wichterle, Hynek; Stein, Joel; Doetsch, Fiona K.; Henderson, Christopher E.

    2014-01-01

    Given their capacity to regenerate cells lost through injury or disease, stem cells offer new vistas into possible treatments for degenerative diseases and their underlying causes. As such, stem cell biology is emerging as a driving force behind many studies in the field of regenerative medicine. This review focuses on our current understanding of the applications of stem cells in treating ailments of the human brain, with an emphasis on neurodegenerative diseases. Two types of neural stem cells are discussed: endogenous neural stem cells residing within the adult brain, and pluripotent stem cells capable of forming neural cells in culture. Endogenous neural stem cells give rise to neurons throughout life, but they are restricted to specialized regions in the brain. Elucidating the molecular mechanisms regulating these cells is key in determining their therapeutic potential, as well as finding mechanisms to activate dormant stem cells outside of these specialized microdomains. In parallel, patient-derived stem cells can be used to generate neural cells in culture, providing new tools for disease modeling, drug testing and cell-based therapies. Turning these technologies into viable treatments will require the integration of basic science with clinical skills in rehabilitation. PMID:24800720

  1. Engineering Stem Cells for Biomedical Applications.

    PubMed

    Yin, Perry T; Han, Edward; Lee, Ki-Bum

    2016-01-01

    Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer.

  2. Stressed stem cells: Temperature response in aged mesenchymal stem cells.

    PubMed

    Stolzing, Alexandra; Sethe, Sebastian; Scutt, Andrew M

    2006-08-01

    Mesenchymal stem cells (MSCs) derived from young (6 week) and aged (56 week) Wistar rats were cultured at standard (37 degrees C) and reduced (32 degrees C) temperature and compared for age markers and stress levels. (ROS, NO, TBARS, carbonyls, lipofuscin, SOD, GPx, apoptosis, proteasome activity) and heat shock proteins (HSP27, -60, -70, -90). Aged MSCs display many of the stress markers associated with aging in other cell types, but results vary across marker categories and are temperature dependant. In young MSCs, culturing at reduced temperature had a generally beneficial effect: the anti-apoptotic heat shock proteins HSP 27, HSP70, and HSP90 were up-regulated; pro-apoptotic HSP60 was downregulated; SOD, GPx increased; and levels in ROS, NO, TBARS, carbonyl, and lipofuscin were diminished. Apoptosis was reduced, but also proteasome activity. In contrast, in aged MSCs, culturing at reduced temperature generally produced no 'beneficial' changes in these parameters, and can even have detrimental effects. Implications for tissue engineering and for stem cell gerontology are discussed. The results suggest that a 'hormesis' theory of stress response can be extended to MSCs, but that cooling cultivation temperature stress produces positive effects in young cells only.

  3. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    SciTech Connect

    Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva; Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs; Apati, Agota

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  4. Reforming craniofacial orthodontics via stem cells

    PubMed Central

    Mohanty, Pritam; Prasad, N.K.K.; Sahoo, Nivedita; Kumar, Gunjan; Mohanty, Debapreeti; Sah, Sushila

    2015-01-01

    Stem cells are the most interesting cells in cell biology. They have the potential to evolve as one of the most powerful technologies in the future. The future refers to an age where it will be used extensively in various fields of medical and dental sciences. Researchers have discovered a number of sources from which stem cells can be derived. Craniofacial problems are very common and occur at all ages. Stem cells can be used therapeutically in almost every field of health science. In fact, many procedures will be reformed after stem cells come into play. This article is an insight into the review of the current researches being carried out on stem cells and its use in the field of orthodontics, which is a specialized branch of dentistry. Although the future is uncertain, there is a great possibility that stem cells will be used extensively in almost all major procedures of orthodontics. PMID:25767761

  5. Dependence of stem cell fate in Arabidopsis on a feedback loop regulated by CLV3 activity.

    PubMed

    Brand, U; Fletcher, J C; Hobe, M; Meyerowitz, E M; Simon, R

    2000-07-28

    The fate of stem cells in plant meristems is governed by directional signaling systems that are regulated by negative feedback. In Arabidopsis thaliana, the CLAVATA (CLV) genes encode the essential components of a negative, stem cell-restricting pathway. We used transgenic plants overexpressing CLV3 to show that meristem cell accumulation and fate depends directly on the level of CLV3 activity and that CLV3 signaling occurs exclusively through a CLV1/CLV2 receptor kinase complex. We also demonstrate that the CLV pathway acts by repressing the activity of the transcription factor WUSCHEL, an element of the positive, stem cell-promoting pathway. PMID:10915624

  6. Stem Cells in the Cornea.

    PubMed

    Hertsenberg, Andrew J; Funderburgh, James L

    2015-01-01

    The cornea is the tough, transparent tissue through which light first enters the eye and functions as a barrier to debris and infection as well as two-thirds of the refractive power of the eye. Corneal damage that is not promptly treated will often lead to scarring and vision impairment. Due to the limited options currently available to treat corneal scars, the identification and isolation of stem cells in the cornea has received much attention, as they may have potential for autologous, cell-based approaches to the treatment of damaged corneal tissue.

  7. Stem cell differentiation and human liver disease

    PubMed Central

    Zhou, Wen-Li; Medine, Claire N; Zhu, Liang; Hay, David C

    2012-01-01

    Human stem cells are scalable cell populations capable of cellular differentiation. This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells. Such an approach has the potential to improve our understanding of human biology and treating disease. In the future it may be possible to deploy novel stem cell-based approaches to treat human liver diseases. In recent years, efficient hepatic differentiation from human stem cells has been achieved by several research groups including our own. In this review we provide an overview of the field and discuss the future potential and limitations of stem cell technology. PMID:22563188

  8. Adult Stem Cell Responses to Nanostimuli

    PubMed Central

    Tsimbouri, Penelope M.

    2015-01-01

    Adult or mesenchymal stem cells (MSCs) have been found in different tissues in the body, residing in stem cell microenvironments called “stem cell niches”. They play different roles but their main activity is to maintain tissue homeostasis and repair throughout the lifetime of an organism. Their ability to differentiate into different cell types makes them an ideal tool to study tissue development and to use them in cell-based therapies. This differentiation process is subject to both internal and external forces at the nanoscale level and this response of stem cells to nanostimuli is the focus of this review. PMID:26193326

  9. Stem cells and the Planarian Schmidtea mediterranea.

    PubMed

    Sánchez Alvarado, Alejandro

    2007-01-01

    In recent years, stem cells have been heralded as potential therapeutic agents to address a large number of degenerative diseases. Yet, in order to rationally utilize these cells as effective therapeutic agents, and/or improve treatment of stem-cell-associated malignancies such as leukemias and carcinomas, a better understanding of the basic biological properties of stem cells needs to be acquired. A major limitation in the study of stem cells lies in the difficulty of accessing and studying these cells in vivo. This barrier is further compounded by the limitations of in vitro culture systems, which are unable to emulate the microenvironments in which stem cells reside and which are known to provide critical regulatory signals for their proliferation and differentiation. Given the complexity of vertebrate embryonic and adult stem cell populations and their relative inaccessibility to in vivo molecular analyses, the study of stem cells should benefit from analyzing their counterparts in simpler model organisms. In the past, the use of Drosophila or C. elegans has provided invaluable contributions to our understanding of genes and pathways involved in a variety of human diseases. However, stem cells in these organisms are mostly restricted to the gonads, and more importantly neither Drosophila, nor C. elegans are capable of regenerating body parts lost to injury. Therefore, a simple animal with experimentally accessible stem cells playing a role in tissue maintenance and/or regeneration should be very useful in identifying and functionally testing the mechanisms regulating stem cell activities. The planarian Schmidtea mediterranea is poised to fill this experimental gap. S. mediterranea displays robust regenerative properties driven by a stem cell population capable of producing the approximately 40 different cell types found in this organism, including the germ cells. Given that all known metazoans depend on stem cells for their survival, it is extremely likely that

  10. Cx43 expression and function in the nervous system—implications for stem cell mediated regeneration

    PubMed Central

    Meier, Carola; Rosenkranz, Katja

    2014-01-01

    Pathological conditions of the brain such as ischemia cause major sensorimotor and cognitive impairments. In novel therapeutic approaches to brain injury, stem cells have been applied to ameliorate the pathological outcome. In several experimental models, including hypoxia-ischemia and trauma, transplantation of stem cells correlated with an improved functional and structural outcome. At the cellular level, brain insults also change gap junction physiology and expression, leading to altered intercellular communication. Differences in expression in response to brain injury have been detected in particular in Cx43, the major astrocytic gap junction protein, and its overexpression or deletion was associated with the pathophysiological outcome. We here focus on Cx43 changes in host tissue mediated by stem cells. Stem cell-induced changes in connexin expression, and consecutively in gap junction channel or hemichannel function, might play a part in altered cell interaction, intercellular communication, and neural cell survival, and thereby contribute to the beneficial effects of transplanted stem cells. PMID:24672489

  11. 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

  12. Induction of tissue-specific stem cells by reprogramming factors, and tissue-specific selection.

    PubMed

    Noguchi, H; Saitoh, I; Tsugata, T; Kataoka, H; Watanabe, M; Noguchi, Y

    2015-01-01

    Although induced pluripotent stem (iPS) cells have significant implications for overcoming most of the ethical issues associated with embryonic stem (ES) cells, there are still several unresolved issues related to the use of iPS cells for clinical applications, such as teratoma formation. In this study, we were able to generate tissue-specific stem (induced tissue-specific stem; iTS) cells from the pancreas (iTS-P) or liver (iTS-L) by transient overexpression of reprogramming factors, combined with tissue-specific selection. The generation of iTS cells was easier than that of iPS cells. The iTS-P/iTS-L cells express genetic markers of endoderm and pancreatic/hepatic progenitors and were able to differentiate into insulin-producing cells/hepatocytes more efficiently than ES cells. Subcutaneous transplantation of both types of iTS cells into immunodeficient mice resulted in no teratoma formation. The technology used for the transient overexpression of reprogramming factors and tissue-specific selection may be useful for the generation of other tissue-specific stem cells, and the generation of iTS cells could have important implications for the clinical application of stem cells.

  13. Induction of tissue-specific stem cells by reprogramming factors, and tissue-specific selection.

    PubMed

    Noguchi, H; Saitoh, I; Tsugata, T; Kataoka, H; Watanabe, M; Noguchi, Y

    2015-01-01

    Although induced pluripotent stem (iPS) cells have significant implications for overcoming most of the ethical issues associated with embryonic stem (ES) cells, there are still several unresolved issues related to the use of iPS cells for clinical applications, such as teratoma formation. In this study, we were able to generate tissue-specific stem (induced tissue-specific stem; iTS) cells from the pancreas (iTS-P) or liver (iTS-L) by transient overexpression of reprogramming factors, combined with tissue-specific selection. The generation of iTS cells was easier than that of iPS cells. The iTS-P/iTS-L cells express genetic markers of endoderm and pancreatic/hepatic progenitors and were able to differentiate into insulin-producing cells/hepatocytes more efficiently than ES cells. Subcutaneous transplantation of both types of iTS cells into immunodeficient mice resulted in no teratoma formation. The technology used for the transient overexpression of reprogramming factors and tissue-specific selection may be useful for the generation of other tissue-specific stem cells, and the generation of iTS cells could have important implications for the clinical application of stem cells. PMID:25190146

  14. Semaphorin 3A Induces Mesenchymal-Stem-Like Properties in Human Periodontal Ligament Cells

    PubMed Central

    Maeda, Hidefumi; Hasegawa, Daigaku; Gronthos, Stan; Bartold, Peter Mark; Menicanin, Danijela; Fujii, Shinsuke; Yoshida, Shinichiro; Tomokiyo, Atsushi; Monnouchi, Satoshi; Akamine, Akifumi

    2014-01-01

    Periodontal ligament stem cells (PDLSCs) have recently been proposed as a novel option in periodontal regenerative therapy. However, one of the issues is the difficulty of stably generating PDLSCs because of the variation of stem cell potential between donors. Here, we show that Semaphorin 3A (Sema3A) can induce mesenchymal-stem-like properties in human periodontal ligament (PDL) cells. Sema3A expression was specifically observed in the dental follicle during tooth development and in parts of mature PDL tissue in rodent tooth and periodontal tissue. Sema3A expression levels were found to be higher in multipotential human PDL cell clones compared with low-differentiation potential clones. Sema3A-overexpressing PDL cells exhibited an enhanced capacity to differentiate into both functional osteoblasts and adipocytes. Moreover, PDL cells treated with Sema3A only at the initiation of culture stimulated osteogenesis, while Sema3A treatment throughout the culture had no effect on osteogenic differentiation. Finally, Sema3A-overexpressing PDL cells upregulated the expression of embryonic stem cell markers (NANOG, OCT4, and E-cadherin) and mesenchymal stem cell markers (CD73, CD90, CD105, CD146, and CD166), and Sema3A promoted cell division activity of PDL cells. These results suggest that Sema3A may possess the function to convert PDL cells into mesenchymal-stem-like cells. PMID:24380401

  15. Promise of cancer stem cell vaccine

    PubMed Central

    Zhou, Li; Lu, Lin; Wicha, Max S; Chang, Alfred E; Xia, Jian-chuan; Ren, Xiubao; Li, Qiao

    2015-01-01

    Dendritic cell (DC)-based vaccines designed to target cancer stem cells (CSC) can induce significant antitumor responses via conferring host anti-CSC immunity. Our recent studies have demonstrated that CSC-DC vaccine could inhibit metastasis of primary tumors and induce humoral immune responses against cancer stem cells. This approach highlights the promise of cancer stem cell vaccine in cancer immunotherapy. PMID:26337078

  16. Stem Cells in Teeth and Craniofacial Bones

    PubMed Central

    Zhao, H.; Chai, Y.

    2015-01-01

    Stem cells are remarkable, and stem cell–based tissue engineering is an emerging field of biomedical science aiming to restore damaged tissue or organs. In dentistry and reconstructive facial surgery, it is of great interest to restore lost teeth or craniofacial bone defects using stem cell–mediated therapy. In the craniofacial region, various stem cell populations have been identified with regeneration potential. In this review, we provide an overview of the current knowledge concerning the various types of tooth- and craniofacial bone–related stem cells and discuss their in vivo identities and regulating mechanisms. PMID:26350960

  17. [Advances in Lung Stem Cells and Lung Cancer Stem Cells].

    PubMed

    Yin, Huijing; Deng, Jiong

    2015-10-20

    Cancer stem cells (CSCs) are emerging as a hot topic for cancer research. Lung CSCs share many characteristics with normal lung stem cells (SCs), including self-renewal and multi-potency for differentiation. Many molecular markers expressed in various types of CSCs were also found in lung CSCs, such as CD133, CD44, aldehyde dehydrogenase (ALDH) and ATP-binding cassette sub-family G member 2 (ABCG2). Similarly, proliferation and expansion of lung CSCs are regulated not only by signal transduction pathways functioning in normal lung SCs, such as Notch, Hedgehog and Wnt pathways, but also by those acting in tumor cells, such as epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT3) and phosphatidylinositol 3 kinase (PI3K) pathways. As CSC plays an critical role in tumor recurrence, metastasis and drug-resistance, understanding the difference between lung CSCs and normal lung SCs, identifying and targeting CSC markers or related signaling pathways may increase the efficacy of therapy on lung cancer and improved survival of lung cancer patients.

  18. Mammary stem cells have myoepithelial cell properties

    PubMed Central

    Prater, Michael D.; Petit, Valérie; Russell, I. Alasdair; Giraddi, Rajshekhar; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F.; Metzger, Daniel; Faraldo, Marisa M.; Deugnier, Marie-Ange; Glukhova, Marina A.; Stingl, John

    2014-01-01

    Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt acin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using 2 independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage tracing approach we follow the progeny of α-smooth muscle actin-expressing myoepithelial cells and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy. PMID:25173976

  19. Therapeutic potential of amniotic fluid stem cells.

    PubMed

    Abdulrazzak, Hassan; De Coppi, Paolo; Guillot, Pascale V

    2013-03-01

    Human amniotic fluid cells have been used traditionally as a diagnostic tool for genetic anomalies. More recently it has been recognized that amniotic fluid contains populations of stem cells. Mesenchymal stem cells (AFMSC) were first to be described. These cells are able to differentiate towards mesodermal lineages. More recently cells with broader potential, defined as amniotic fluid stem cells (AFSC), were also isolated. They have intermediate characteristics between embryonic and adult stem cells and are able to differentiate into lineages representative of all three germ layers but unlike ES cells they do not form tumours in vivo. Furthermore, AFSC have been reverted to functional pluripotency in a transgene-free approach using an epigenetics modifier. These characteristics, together with absence of ethical issues concerning their employment, have made stem cells from amniotic fluid a promising candidate for cell therapy and tissue engineering.

  20. Identification of stem-like cells and clinical significance of candidate stem cell markers in gastric cancer

    PubMed Central

    Wang, Xiaofeng; Huang, Mingzhu; Gan, Lu; Wu, Zhenhua; Zhang, Jiejun; Wang, Hongqiang; Cheng, Yufan; Li, Jin; Guo, Weijian

    2016-01-01

    The existence of gastric cancer stem cells (CSCs) has not been definitively proven and specific cell surface markers for identifying gastric CSCs have largely not been identified. Our research aimed to isolate potential gastric CSCs and clarify their clinical significance, while defining markers for GCSC identification and verification. Here, we report that spheroid cells possess stem cell-like properties, and overexpress certain stem cell markers. CD133 or CD44-positive cells also exhibit properties of CSCs. The expression of Oct4, Sox2, Gli1, CD44, CD133, p-AKT, and p-ERK was significantly higher in metastatic lesions compared to that in primary lesions. Elevated expression of some of these proteins was correlated with a more aggressive phenotype and poorer prognosis, including Oct4, Sox2, Gli1, CD44, and p-ERK. Multivariate Cox proportional hazards model analysis showed that only CD44 is an independent factor. Knockdown of CD44 down-regulated the stem cell-like properties, which was accompanied by the down-regulation of p-ERK and Oct4. Oct4 overexpression could reverse the decreased CSCs properties induced by CD44 knockdown. Taken together, our research revealed that spheroid cell culture, and CD133 or CD44-labeled FACS methods can be used to isolate gastric CSCs. Some CSC markers have clinical significance in predicting the prognosis. CD44 is an independent prognostic factor and maintains the properties of CSCs in CD44-p-ERK-Oct4 positive feedback loop. PMID:26769843

  1. Stem Cell Therapy for Autism

    PubMed Central

    Ichim, Thomas E; Solano, Fabio; Glenn, Eduardo; Morales, Frank; Smith, Leonard; Zabrecky, George; Riordan, Neil H

    2007-01-01

    Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions whose incidence is reaching epidemic proportions, afflicting approximately 1 in 166 children. Autistic disorder, or autism is the most common form of ASD. Although several neurophysiological alterations have been associated with autism, immune abnormalities and neural hypoperfusion appear to be broadly consistent. These appear to be causative since correlation of altered inflammatory responses, and hypoperfusion with symptology is reported. Mesenchymal stem cells (MSC) are in late phases of clinical development for treatment of graft versus host disease and Crohn's Disease, two conditions of immune dysregulation. Cord blood CD34+ cells are known to be potent angiogenic stimulators, having demonstrated positive effects in not only peripheral ischemia, but also in models of cerebral ischemia. Additionally, anecdotal clinical cases have reported responses in autistic children receiving cord blood CD34+ cells. We propose the combined use of MSC and cord blood CD34+cells may be useful in the treatment of autism. PMID:17597540

  2. Multiple Myeloma Cancer Stem Cells

    PubMed Central

    Huff, Carol Ann; Matsui, William

    2008-01-01

    Multiple myeloma is characterized by the clonal expansion of neoplastic plasma cells within the bone marrow, elevated serum immunoglobulin, and osteolytic bone disease. The disease is highly responsive to a wide variety of anticancer treatments including conventional cytotoxic chemotherapy, corticosteroids, radiation therapy, and a growing number of agents with novel mechanisms of action. However, few if any patients are cured with these modalities and relapse remains a critical issue. A better understanding of clonogenic multiple myleoma cells is essential to ultimately improving long-term outcomes, but the nature of the cells responsible for myeloma regrowth and disease relapse is unclear. We review evidence that functional heterogeneity exists in multiple myeloma and discuss potential strategies and clinical implications of the stem-cell model of cancer in this disease. PMID:18539970

  3. Stem cell therapy for autism.

    PubMed

    Ichim, Thomas E; Solano, Fabio; Glenn, Eduardo; Morales, Frank; Smith, Leonard; Zabrecky, George; Riordan, Neil H

    2007-06-27

    Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions whose incidence is reaching epidemic proportions, afflicting approximately 1 in 166 children. Autistic disorder, or autism is the most common form of ASD. Although several neurophysiological alterations have been associated with autism, immune abnormalities and neural hypoperfusion appear to be broadly consistent. These appear to be causative since correlation of altered inflammatory responses, and hypoperfusion with symptology is reported. Mesenchymal stem cells (MSC) are in late phases of clinical development for treatment of graft versus host disease and Crohn's Disease, two conditions of immune dysregulation. Cord blood CD34+ cells are known to be potent angiogenic stimulators, having demonstrated positive effects in not only peripheral ischemia, but also in models of cerebral ischemia. Additionally, anecdotal clinical cases have reported responses in autistic children receiving cord blood CD34+ cells. We propose the combined use of MSC and cord blood CD34+cells may be useful in the treatment of autism.

  4. Conditionally reprogrammed cells represent a stem-like state of adult epithelial cells

    PubMed Central

    Suprynowicz, Frank A.; Upadhyay, Geeta; Krawczyk, Ewa; Kramer, Sarah C.; Hebert, Jess D.; Liu, Xuefeng; Yuan, Hang; Cheluvaraju, Chaitra; Clapp, Phillip W.; Boucher, Richard C.; Kamonjoh, Christopher M.; Randell, Scott H.; Schlegel, Richard

    2012-01-01

    The combination of irradiated fibroblast feeder cells and Rho kinase inhibitor, Y-27632, conditionally induces an indefinite proliferative state in primary mammalian epithelial cells. These conditionally reprogrammed cells (CRCs) are karyotype-stable and nontumorigenic. Because self-renewal is a recognized property of stem cells, we investigated whether Y-27632 and feeder cells induced a stem-like phenotype. We found that CRCs share characteristics of adult stem cells and exhibit up-regulated expression of α6 and β1 integrins, ΔNp63α, CD44, and telomerase reverse transcriptase, as well as decreased Notch signaling and an increased level of nuclear β-catenin. The induction of CRCs is rapid (occurs within 2 d) and results from reprogramming of the entire cell population rather than the selection of a minor subpopulation. CRCs do not overexpress the transcription factor sets characteristic of embryonic or induced pluripotent stem cells (e.g., Sox2, Oct4, Nanog, or Klf4). The induction of CRCs is also reversible, and removal of Y-27632 and feeders allows the cells to differentiate normally. Thus, when CRCs from ectocervical epithelium or tracheal epithelium are placed in an air–liquid interface culture system, the cervical cells form a well differentiated stratified squamous epithelium, whereas the tracheal cells form a ciliated airway epithelium. We discuss the diagnostic and therapeutic opportunities afforded by a method that can generate adult stem-like cells in vitro without genetic manipulation. PMID:23169653

  5. Establishment of a Mesenchymal Stem Cell Bank

    PubMed Central

    Cooper, Khushnuma; Viswanathan, Chandra

    2011-01-01

    Adult stem cells have generated great amount of interest amongst the scientific community for their potential therapeutic applications for unmet medical needs. We have demonstrated the plasticity of mesenchymal stem cells isolated from the umbilical cord matrix. Their immunological profile makes it even more interesting. We have demonstrated that the umbilical cord is an inexhaustible source of mesenchymal stem cells. Being a very rich source, instead of discarding this tissue, we worked on banking these cells for regenerative medicine application for future use. The present paper gives a detailed account of our experience in the establishment of a mesenchymal stem cell bank at our facility. PMID:21826152

  6. Mesenchymal Stem Cells in Cardiology.

    PubMed

    White, Ian A; Sanina, Cristina; Balkan, Wayne; Hare, Joshua M

    2016-01-01

    Cardiovascular disease (CVD) accounts for more deaths globally than any other single disease. There are on average 1.5 million episodes of myocardial infarction (heart attack) each year in the United States alone with roughly one-third resulting in death. There is therefore a major need for developing new and effective strategies to promote cardiac repair. Intramyocardial transplantation of mesenchymal stem cells (MSCs) has emerged as a leading contender in the pursuit of clinical intervention and therapy. MSCs are potent mediators of cardiac repair and are therefore an attractive tool in the development of preclinical and clinical trials. MSCs are capable of secreting a large array of soluble factors, which have had demonstrated effects on pathogenic cardiac remolding, fibrosis, immune activation, and cardiac stem cell proliferation within the damaged heart. MSCs are also capable of differentiation into cardiomyocytes, endothelial cells, and vascular smooth muscle cells, although the relative contribution of trilineage differentiation and paracrine effectors on cardiac repair remains the subject of active investigation. PMID:27236666

  7. Patenting human genes and stem cells.

    PubMed

    Martin-Rendon, Enca; Blake, Derek J

    2007-01-01

    Cell lines and genetically modified single cell organisms have been considered patentable subjects for the last two decades. However, despite the technical patentability of genes and stem cell lines, social and legal controversy concerning their 'ownership' has surrounded stem cell research in recent years. Some granted patents on stem cells with extremely broad claims are casting a shadow over the commercialization of these cells as therapeutics. However, in spite of those early patents, the number of patent applications related to stem cells is growing exponentially. Both embryonic and adult stem cells have the ability to differentiate into several cell lineages in an organism as a result of specific genetic programs that direct their commitment and cell fate. Genes that control the pluripotency of stem cells have been recently identified and the genetic manipulation of these cells is becoming more efficient with the advance of new technologies. This review summarizes some of the recent published patents on pluripotency genes, gene transfer into stem cells and genetic reprogramming and takes the hematopoietic and embryonic stem cell as model systems.

  8. Overexpression of Ref-1 Inhibits Lead-induced Endothelial Cell Death via the Upregulation of Catalase.

    PubMed

    Lee, Kwon Ho; Lee, Sang Ki; Kim, Hyo Shin; Cho, Eun Jung; Joo, Hee Kyoung; Lee, Eun Ji; Lee, Ji Young; Park, Myoung Soo; Chang, Seok Jong; Cho, Chung-Hyun; Park, Jin Bong; Jeon, Byeong Hwa

    2009-12-01

    The role of apurinic/apyrimidinic endonuclease1/redox factor-1 (Ref-1) on the lead (Pb)-induced cellular response was investigated in the cultured endothelial cells. Pb caused progressive cellular death in endothelial cells, which occurred in a concentration- and time-dependent manner. However, Ref-1 overexpression with AdRef-1 significantly inhibited Pb-induced cell death in the endothelial cells. Also the overexpression of Ref-1 significantly suppressed Pb-induced superoxide and hydrogen peroxide elevation in the endothelial cells. Pb exposure induced the downregulation of catalase, it was inhibited by the Ref-1 overexpression in the endothelial cells. Taken together, our data suggests that the overexpression of Ref-1 inhibited Pb-induced cell death via the upregulation of catalase in the cultured endothelial cells.

  9. Overexpression of Ref-1 Inhibits Lead-induced Endothelial Cell Death via the Upregulation of Catalase

    PubMed Central

    Lee, Kwon Ho; Lee, Sang Ki; Kim, Hyo Shin; Cho, Eun Jung; Joo, Hee Kyoung; Lee, Eun Ji; Lee, Ji Young; Park, Myoung Soo; Chang, Seok Jong; Cho, Chung-Hyun; Park, Jin Bong

    2009-01-01

    The role of apurinic/apyrimidinic endonuclease1/redox factor-1 (Ref-1) on the lead (Pb)-induced cellular response was investigated in the cultured endothelial cells. Pb caused progressive cellular death in endothelial cells, which occurred in a concentration- and time-dependent manner. However, Ref-1 overexpression with AdRef-1 significantly inhibited Pb-induced cell death in the endothelial cells. Also the overexpression of Ref-1 significantly suppressed Pb-induced superoxide and hydrogen peroxide elevation in the endothelial cells. Pb exposure induced the downregulation of catalase, it was inhibited by the Ref-1 overexpression in the endothelial cells. Taken together, our data suggests that the overexpression of Ref-1 inhibited Pb-induced cell death via the upregulation of catalase in the cultured endothelial cells. PMID:20054488

  10. Stem cells in the light of evolution

    PubMed Central

    Chakraborty, Chiranjib; Agoramoorthy, Govindasamy

    2012-01-01

    All organisms depend on stem cells for their survival. As a result, stem cells may be a prerequisite for the evolution of specific characteristics in organisms that include regeneration, multicellularity and coloniality. Stem cells have attracted the attention of biologists and medical scientists for a long time. These provide materials for regenerative medicine. We review in this paper, the link between modern stem cell research and early studies in ancient organisms. It also outlines details on stem cells in the light of evolution with an emphasis on their regeneration potential, coloniality and multicellularity. The information provided might be of use to molecular biologists, medical scientists and developmental biologists who are engaged in integrated research involving the stem cells. PMID:22825600

  11. Two-photon imaging of stem cells

    NASA Astrophysics Data System (ADS)

    Uchugonova, A.; Gorjup, E.; Riemann, I.; Sauer, D.; König, K.

    2008-02-01

    A variety of human and animal stem cells (rat and human adult pancreatic stem cells, salivary gland stem cells, dental pulpa stem cells) have been investigated by femtosecond laser 5D two-photon microscopy. Autofluorescence and second harmonic generation have been imaged with submicron spatial resolution, 270 ps temporal resolution, and 10 nm spectral resolution. In particular, NADH and flavoprotein fluorescence was detected in stem cells. Major emission peaks at 460nm and 530nm with typical mean fluorescence lifetimes of 1.8 ns and 2.0 ns, respectively, were measured using time-correlated single photon counting and spectral imaging. Differentiated stem cells produced the extracellular matrix protein collagen which was detected by SHG signals at 435 nm.

  12. Stem cell niche engineering through droplet microfluidics.

    PubMed

    Allazetta, Simone; Lutolf, Matthias P

    2015-12-01

    Stem cells reside in complex niches in which their behaviour is tightly regulated by various biochemical and biophysical signals. In order to unveil some of the crucial stem cell-niche interactions and expedite the implementation of stem cells in clinical and pharmaceutical applications, in vitro methodologies are being developed to reconstruct key features of stem cell niches. Recently, droplet-based microfluidics has emerged as a promising strategy to build stem cell niche models in a miniaturized and highly precise fashion. This review highlights current advances in using droplet microfluidics in stem cell biology. We also discuss recent efforts in which microgel technology has been interfaced with high-throughput analyses to engender screening paradigms with an unparalleled potential for basic and applied biological studies.

  13. Of Microenvironments and Mammary Stem Cells

    SciTech Connect

    LaBarge, Mark A; Petersen, Ole W; Bissell, Mina J

    2007-06-01

    In most adult tissues there reside pools of stem and progenitor cells inside specialized microenvironments referred to as niches. The niche protects the stem cells from inappropriate expansion and directs their critical functions. Thus guided, stem cells are able to maintain tissue homeostasis throughout the ebb and flow of metabolic and physical demands encountered over a lifetime. Indeed, a pool of stem cells maintains mammary gland structure throughout development, and responds to the physiological demands associated with pregnancy. This review discusses how stem cells were identified in both human and mouse mammary glands; each requiring different techniques that were determined by differing biological needs and ethical constraints. These studies together create a robust portrait of mammary gland biology and identify the location of the stem cell niche, elucidate a developmental hierarchy, and suggest how the niche might be manipulated for therapeutic benefit.

  14. Fueling Hope: Stem Cells in Social Media.

    PubMed

    Robillard, Julie M; Cabral, Emanuel; Hennessey, Craig; Kwon, Brian K; Illes, Judy

    2015-08-01

    Social media is broadening opportunities to engage in discussions about biomedical advances such as stem cell research. However, little is known about how information pertaining to stem cells is disseminated on platforms such as Twitter. To fill this gap, we conducted a content analysis of tweets containing (i) a stem cell keyword, and (ii) a keyword related to either spinal cord injury (SCI) or Parkinson disease (PD). We found that the discussion about stem cells and SCI or PD revolves around different aspects of the research process. We also found that the tone of most tweets about stem cells is either positive or neutral. The findings contribute new knowledge about Twitter as a connecting platform for many voices and as a key tool for the dissemination of information about stem cells and disorders of the central nervous system.

  15. Role of stem cells in tooth bioengineering

    PubMed Central

    Singh, Kamleshwar; Mishra, Niraj; Kumar, Lakshya; Agarwal, Kaushal Kishore; Agarwal, Bhaskar

    2012-01-01

    The creation of teeth in the laboratory depends upon the manipulation of stem cells and requires a synergy of all cellular and molecular events that finally lead to the formation of tooth-specific hard tissues, dentin, and enamel. This review focuses on the different sources of stem cells that have been used for making teeth in vitro. The search was performed from 1970 to 2012 and was limited to English language papers. The keywords searched on medline were ‘stem cells and dentistry,’ ‘stem cells and odontoblast,’ ‘stem cells and dentin,’ and ‘stem cells and ameloblasts.’ PMID:25756031

  16. YAP/TAZ enhance mammalian embryonic neural stem cell characteristics in a Tead-dependent manner

    SciTech Connect

    Han, Dasol; Byun, Sung-Hyun; Park, Soojeong; Kim, Juwan; Kim, Inhee; Ha, Soobong; Kwon, Mookwang; Yoon, Keejung

    2015-02-27

    Mammalian brain development is regulated by multiple signaling pathways controlling cell proliferation, migration and differentiation. Here we show that YAP/TAZ enhance embryonic neural stem cell characteristics in a cell autonomous fashion using diverse experimental approaches. Introduction of retroviral vectors expressing YAP or TAZ into the mouse embryonic brain induced cell localization in the ventricular zone (VZ), which is the embryonic neural stem cell niche. This change in cell distribution in the cortical layer is due to the increased stemness of infected cells; YAP-expressing cells were colabeled with Sox2, a neural stem cell marker, and YAP/TAZ increased the frequency and size of neurospheres, indicating enhanced self-renewal- and proliferative ability of neural stem cells. These effects appear to be TEA domain family transcription factor (Tead)–dependent; a Tead binding-defective YAP mutant lost the ability to promote neural stem cell characteristics. Consistently, in utero gene transfer of a constitutively active form of Tead2 (Tead2-VP16) recapitulated all the features of YAP/TAZ overexpression, and dominant negative Tead2-EnR resulted in marked cell exit from the VZ toward outer cortical layers. Taken together, these results indicate that the Tead-dependent YAP/TAZ signaling pathway plays important roles in neural stem cell maintenance by enhancing stemness of neural stem cells during mammalian brain development. - Highlights: • Roles of YAP and Tead in vivo during mammalian brain development are clarified. • Expression of YAP promotes embryonic neural stem cell characteristics in vivo in a cell autonomous fashion. • Enhancement of neural stem cell characteristics by YAP depends on Tead. • Transcriptionally active form of Tead alone can recapitulate the effects of YAP. • Transcriptionally repressive form of Tead severely reduces stem cell characteristics.

  17. [Stem cell therapy for neurodegenerative disorders].

    PubMed

    Meyer, Morten; Jensen, Pia; Rasmussen, Jens Zimmer

    2010-09-20

    Intrastriatal, foetal neural transplants can ameliorate symptoms in patients with Parkinson's and Huntington's disease, although not stop the primary cell-loss. Several issues must, however, be addressed before general or extended clinical use of cell therapy in neurodegenerative diseases can become a reality. Improvements include standardized and safe master cell-lines derived from human embryonic stem cells, induced pluripotent stem cells and neural stem cells. Cells from these sources are expected to become available for cell replacement therapies or therapeutic production of trophic, anti-inflammatory and restorative factors within a few years.

  18. Human stem cells and articular cartilage regeneration.

    PubMed

    Inui, Atsuyuki; Iwakura, Takashi; Reddi, A Hari

    2012-11-05

    The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES) cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS) cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  19. [Bioethical challenges of stem cell tourism].

    PubMed

    Ventura-Juncá, Patricio; Erices, Alejandro; Santos, Manuel J

    2013-08-01

    Stem cells have drawn extraordinary attention from scientists and the general public due to their potential to generate effective therapies for incurable diseases. At the same time, the production of embryonic stem cells involves a serious ethical issue concerning the destruction of human embryos. Although adult stem cells and induced pluripotential cells do not pose this ethical objection, there are other bioethical challenges common to all types of stem cells related particularly to the clinical use of stem cells. Their clinical use should be based on clinical trials, and in special situations, medical innovation, both of which have particular ethical dimensions. The media has raised unfounded expectations in patients and the public about the real clinical benefits of stem cells. At the same time, the number of unregulated clinics is increasing around the world, making direct offers through Internet of unproven stem cell therapies that attract desperate patients that have not found solutions in standard medicine. This is what is called stem cells tourism. This article reviews this situation, its consequences and the need for international cooperation to establish effective regulations to prevent the exploitation of patients and to endanger the prestige of legitimate stem cell research.

  20. miR-381 Regulates Neural Stem Cell Proliferation and Differentiation via Regulating Hes1 Expression

    PubMed Central

    Liu, Baoquan; Yang, Chunxiao; Nie, Xuedan; Wang, Xiaokun; Zheng, Jiaolin; Wang, Yue; Zhu, Yulan

    2015-01-01

    Neural stem cells are self-renewing, multipotent and undifferentiated precursors that retain the capacity for differentiation into both glial (astrocytes and oligodendrocytes) and neuronal lineages. Neural stem cells offer cell-based therapies for neurological disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease and spinal cord injuries. However, their cellular behavior is poorly understood. MicroRNAs (miRNAs) are a class of small noncoding RNAs involved in cell development, proliferation and differentiation through regulating gene expression at post-transcriptional level. The role of miR–381 in the development of neural stem cells remains unknown. In this study, we showed that overexpression of miR–381 promoted neural stem cells proliferation. It induced the neural stem cells differentiation to neurons and inhibited their differentiation to astrocytes. Furthermore, we identified HES1 as a direct target of miR–381 in neural stem cells. Moreover, re-expression of HES1 impaired miR-381-induced promotion of neural stem cells proliferation and induce neural stem cells differentiation to neurons. In conclusion, miR–381 played important role in neural stem cells proliferation and differentiation. PMID:26431046

  1. Hoxb4 Overexpression in CD4 Memory Phenotype T Cells Increases the Central Memory Population upon Homeostatic Proliferation

    PubMed Central

    Fournier, Marilaine; Labrecque, Nathalie; Bijl, Janet J.

    2013-01-01

    Memory T cell populations allow a rapid immune response to pathogens that have been previously encountered and thus form the basis of success in vaccinations. However, the molecular pathways underlying the development and maintenance of these cells are only starting to be unveiled. Memory T cells have the capacity to self renew as do hematopoietic stem cells, and overlapping gene expression profiles suggested that these cells might use the same self-renewal pathways. The transcription factor Hoxb4 has been shown to promote self-renewal divisions of hematopoietic stem cells resulting in an expansion of these cells. In this study we investigated whether overexpression of Hoxb4 could provide an advantage to CD4 memory phenotype T cells in engrafting the niche of T cell deficient mice following adoptive transfer. Competitive transplantation experiments demonstrated that CD4 memory phenotype T cells derived from mice transgenic for Hoxb4 contributed overall less to the repopulation of the lymphoid organs than wild type CD4 memory phenotype T cells after two months. These proportions were relatively maintained following serial transplantation in secondary and tertiary mice. Interestingly, a significantly higher percentage of the Hoxb4 CD4 memory phenotype T cell population expressed the CD62L and Ly6C surface markers, characteristic for central memory T cells, after homeostatic proliferation. Thus Hoxb4 favours the maintenance and increase of the CD4 central memory phenotype T cell population. These cells are more stem cell like and might eventually lead to an advantage of Hoxb4 T cells after subjecting the cells to additional rounds of proliferation. PMID:24324706

  2. Telomeres, stem cells, and hematology

    PubMed Central

    2008-01-01

    Telomeres are highly dynamic structures that adjust the cellular response to stress and growth stimulation based on previous cell divisions. This critical function is accomplished by progressive telomere shortening and DNA damage responses activated by chromosome ends without sufficient telomere repeats. Repair of critically short telomeres by telomerase or recombination is limited in most somatic cells, and apoptosis or cellular senescence is triggered when too many uncapped telomeres accumulate. The chance of the latter increases as the average telomere length decreases. The average telomere length is set and maintained in cells of the germ line that typically express high levels of telomerase. In somatic cells, the telomere length typically declines with age, posing a barrier to tumor growth but also contributing to loss of cells with age. Loss of (stem) cells via telomere attrition provides strong selection for abnormal cells in which malignant progression is facilitated by genome instability resulting from uncapped telomeres. The critical role of telomeres in cell proliferation and aging is illustrated in patients with 50% of normal telomerase levels resulting from a mutation in one of the telomerase genes. Here, the role of telomeres and telomerase in human biology is reviewed from a personal historical perspective. PMID:18263784

  3. Stem cell reprogramming: A 3D boost

    NASA Astrophysics Data System (ADS)

    Abilez, Oscar J.; Wu, Joseph C.

    2016-03-01

    Biophysical factors in an optimized three-dimensional microenvironment enhance the reprogramming efficiency of human somatic cells into pluripotent stem cells when compared to traditional cell-culture substrates.

  4. Increased centrosome amplification in aged stem cells of the Drosophila midgut

    SciTech Connect

    Park, Joung-Sun; Pyo, Jung-Hoon; Na, Hyun-Jin; Jeon, Ho-Jun; Kim, Young-Shin; Arking, Robert; Yoo, Mi-Ae

    2014-07-25

    Highlights: • Increased centrosome amplification in ISCs of aged Drosophila midguts. • Increased centrosome amplification in ISCs of oxidative stressed Drosophila midguts. • Increased centrosome amplification in ISCs by overexpression of PVR, EGFR, and AKT. • Supernumerary centrosomes can be responsible for abnormal ISC polyploid cells. • Supernumerary centrosomes can be a useful marker for aging stem cells. - Abstract: Age-related changes in long-lived tissue-resident stem cells may be tightly linked to aging and age-related diseases such as cancer. Centrosomes play key roles in cell proliferation, differentiation and migration. Supernumerary centrosomes are known to be an early event in tumorigenesis and senescence. However, the age-related changes of centrosome duplication in tissue-resident stem cells in vivo remain unknown. Here, using anti-γ-tubulin and anti-PH3, we analyzed mitotic intestinal stem cells with supernumerary centrosomes in the adult Drosophila midgut, which may be a versatile model system for stem cell biology. The results showed increased centrosome amplification in intestinal stem cells of aged and oxidatively stressed Drosophila midguts. Increased centrosome amplification was detected by overexpression of PVR, EGFR, and AKT in intestinal stem cells/enteroblasts, known to mimic age-related changes including hyperproliferation of intestinal stem cells and hyperplasia in the midgut. Our data show the first direct evidence for the age-related increase of centrosome amplification in intestinal stem cells and suggest that the Drosophila midgut is an excellent model for studying molecular mechanisms underlying centrosome amplification in aging adult stem cells in vivo.

  5. Plant stem cells as innovation in cosmetics.

    PubMed

    Moruś, Martyna; Baran, Monika; Rost-Roszkowska, Magdalena; Skotnicka-Graca, Urszula

    2014-01-01

    The stem cells thanks to their ability of unlimited division number or transformation into different cell types creating organs, are responsible for regeneration processes. Depending on the organism in which the stem cells exists, they divide to the plant or animal ones. The later group includes the stem cells existing in both embryo's and adult human's organs. It includes, among others, epidermal stem cells, located in the hair follicle relieves and also in its basal layers, and responsible for permanent regeneration of the epidermis. Temporary science looks for method suitable for stimulation of the epidermis stem cells, amongst the other by delivery of e.g., growth factors for proliferation that decrease with the age. One of the methods is the use of the plant cell culture technology, including a number of methods that should ensure growth of plant cells, issues or organs in the environment with the microorganism-free medium. It uses abilities of the different plant cells to dedifferentiation into stem cells and coming back to the pluripotent status. The extracts obtained this way from the plant stem cells are currently used for production of both common or professional care cosmetics. This work describes exactly impact of the plant stem cell extract, coming from one type of the common apple tree (Uttwiler Spätlauber) to human skin as one of the first plant sorts, which are used in cosmetology and esthetic dermatology.

  6. Prospects of Stem Cells for Retinal Diseases.

    PubMed

    Ng, Tsz Kin; Lam, Dennis S C; Cheung, Herman S

    2013-01-01

    Retinal diseases, including glaucoma, retinitis pigmentosa, diabetic retinopathy, and age-related macular degeneration, are the leading causes of irreversible visual impairment and blindness in developed countries. Traditional and current treatment regimens are based on surgical or medical interventions to slow down the disease progression. However, the number of retinal cells would continue to diminish, and the diseases could not be completely cured. There is an emerging role of stem cells in retinal research. The stem cell therapy on retinal diseases is based on 2 theories: cell replacement therapy and neuroprotective effect. The former hypothesizes that new retinal cells could be regenerated from stem cells to substitute the damaged cells in the diseased retina, whereas the latter believes that the paracrine effects of stem cells modulate the microenvironments of the diseased retina so as to protect the retinal neurons. This article summarizes the choice of stem cells in retinal research. Moreover, the current progress of retinal research on stem cells and the clinical applications of stem cells on retinal diseases are reviewed. In addition, potential challenges and future prospects of retinal stem cell research are discussed.

  7. Burning Fat Fuels Leukemic Stem Cell Heterogeneity.

    PubMed

    Thomas, Daniel; Majeti, Ravindra

    2016-07-01

    Obese leukemia patients exhibit reduced survival after chemotherapy, suggesting an important role of adipose tissue in disease progression. In this issue of Cell Stem Cell, Ye et al. (2016) reveal metabolic heterogeneity in leukemic stem cell (LSC) subpopulations and show that chemotherapy-resistant CD36+ LSCs co-opt gonadal adipose tissue to support their metabolism and survival. PMID:27392217

  8. Ocular stem cells: a status update!

    PubMed Central

    2014-01-01

    Stem cells are unspecialized cells that have been a major focus of the field of regenerative medicine, opening new frontiers and regarded as the future of medicine. The ophthalmology branch of the medical sciences was the first to directly benefit from stem cells for regenerative treatment. The success stories of regenerative medicine in ophthalmology can be attributed to its accessibility, ease of follow-up and the eye being an immune-privileged organ. Cell-based therapies using stem cells from the ciliary body, iris and sclera are still in animal experimental stages but show potential for replacing degenerated photoreceptors. Limbal, corneal and conjunctival stem cells are still limited for use only for surface reconstruction, although they might have potential beyond this. Iris pigment epithelial, ciliary body epithelial and choroidal epithelial stem cells in laboratory studies have shown some promise for retinal or neural tissue replacement. Trabecular meshwork, orbital and sclera stem cells have properties identical to cells of mesenchymal origin but their potential has yet to be experimentally determined and validated. Retinal and retinal pigment epithelium stem cells remain the most sought out stem cells for curing retinal degenerative disorders, although treatments using them have resulted in variable outcomes. The functional aspects of the therapeutic application of lenticular stem cells are not known and need further attention. Recently, embryonic stem cell-derived retinal pigment epithelium has been used for treating patients with Stargardts disease and age-related macular degeneration. Overall, the different stem cells residing in different components of the eye have shown some success in clinical and animal studies in the field of regenerative medicine. PMID:25158127

  9. Ocular stem cells: a status update!

    PubMed

    Dhamodaran, Kamesh; Subramani, Murali; Ponnalagu, Murugeswari; Shetty, Reshma; Das, Debashish

    2014-01-01

    Stem cells are unspecialized cells that have been a major focus of the field of regenerative medicine, opening new frontiers and regarded as the future of medicine. The ophthalmology branch of the medical sciences was the first to directly benefit from stem cells for regenerative treatment. The success stories of regenerative medicine in ophthalmology can be attributed to its accessibility, ease of follow-up and the eye being an immune-privileged organ. Cell-based therapies using stem cells from the ciliary body, iris and sclera are still in animal experimental stages but show potential for replacing degenerated photoreceptors. Limbal, corneal and conjunctival stem cells are still limited for use only for surface reconstruction, although they might have potential beyond this. Iris pigment epithelial, ciliary body epithelial and choroidal epithelial stem cells in laboratory studies have shown some promise for retinal or neural tissue replacement. Trabecular meshwork, orbital and sclera stem cells have properties identical to cells of mesenchymal origin but their potential has yet to be experimentally determined and validated. Retinal and retinal pigment epithelium stem cells remain the most sought out stem cells for curing retinal degenerative disorders, although treatments using them have resulted in variable outcomes. The functional aspects of the therapeutic application of lenticular stem cells are not known and need further attention. Recently, embryonic stem cell-derived retinal pigment epithelium has been used for treating patients with Stargardts disease and age-related macular degeneration. Overall, the different stem cells residing in different components of the eye have shown some success in clinical and animal studies in the field of regenerative medicine.

  10. Hardwiring Stem Cell Communication through Tissue Structure.

    PubMed

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-03-10

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. PMID:26967287

  11. Hardwiring Stem Cell Communication through Tissue Structure.

    PubMed

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-03-10

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function, but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues.

  12. Nanomaterials for Engineering Stem Cell Responses.

    PubMed

    Kerativitayanan, Punyavee; Carrow, James K; Gaharwar, Akhilesh K

    2015-08-01

    Recent progress in nanotechnology has stimulated the development of multifunctional biomaterials for tissue engineering applications. Synergistic interactions between nanomaterials and stem cell engineering offer numerous possibilities to address some of the daunting challenges in regenerative medicine, such as controlling trigger differentiation, immune reactions, limited supply of stem cells, and engineering complex tissue structures. Specifically, the interactions between stem cells and their microenvironment play key roles in controlling stem cell fate, which underlines therapeutic success. However, the interactions between nanomaterials and stem cells are not well understood, and the effects of the nanomaterials shape, surface morphology, and chemical functionality on cellular processes need critical evaluation. In this Review, focus is put on recent development in nanomaterial-stem cell interactions, with specific emphasis on their application in regenerative medicine. Further, the emerging technologies based on nanomaterials developed over the past decade for stem cell engineering are reviewed, as well as the potential applications of these nanomaterials in tissue regeneration, stem cell isolation, and drug/gene delivery. It is anticipated that the enhanced understanding of nanomaterial-stem cell interactions will facilitate improved biomaterial design for a range of biomedical and biotechnological applications.

  13. Wnt Signaling in Cancer Stem Cell Biology.

    PubMed

    de Sousa E Melo, Felipe; Vermeulen, Louis

    2016-06-27

    Aberrant regulation of Wnt signaling is a common theme seen across many tumor types. Decades of research have unraveled the epigenetic and genetic alterations that result in elevated Wnt pathway activity. More recently, it has become apparent that Wnt signaling levels identify stem-like tumor cells that are responsible for fueling tumor growth. As therapeutic targeting of these tumor stem cells is an intense area of investigation, a concise understanding on how Wnt activity relates to cancer stem cell traits is needed. This review attempts at summarizing the intricacies between Wnt signaling and cancer stem cell biology with a special emphasis on colorectal cancer.

  14. Genetic and epigenetic instability of stem cells.

    PubMed

    Rajamani, Karthyayani; Li, Yuan-Sheng; Hsieh, Dean-Kuo; Lin, Shinn-Zong; Harn, Horng-Jyh; Chiou, Tzyy-Wen

    2014-01-01

    Recently, research on stem cells has been receiving an increasing amount of attention, both for its advantages and disadvantages. Genetic and epigenetic instabilities among stem cells have been a recurring obstacle to progress in regenerative medicine using stem cells. Various reports have stated that these instabilities can transform stem cells when transferred in vivo and thus have the potential to develop tumors. Previous research has shown that various extrinsic and intrinsic factors can contribute to the stability of stem cells. The extrinsic factors include growth supplements, growth factors, oxygen tension, passage technique, and cryopreservation. Controlling these factors based on previous reports may assist researchers in developing strategies for the production and clinical application of "safe" stem cells. On the other hand, the intrinsic factors can be unpredictable and uncontrollable; therefore, to ensure the successful use of stem cells in regenerative medicine, it is imperative to develop and implement appropriate strategies and technique for culturing stem cells and to confirm the genetic and epigenetic safety of these stem cells before employing them in clinical trials.

  15. The Patentability of Stem Cells in Australia.

    PubMed

    Petering, Jenny; Cowin, Prue

    2015-07-01

    The potential therapeutic applications of stem cells are unlimited. However, the ongoing political and social debate surrounding the intellectual property and patenting considerations of stem cell research has led to the implementation of strict legislative regulations. In Australia the patent landscape surrounding stem cells has evolved considerably over the past 20 years. The Australian Patents Act 1990 includes a specific exclusion to the patentability of human beings and of biological processes for their generation. However, this exclusion has received no judicial consideration to date, and so its scope and potential impact on stem cell patents is unclear.

  16. Wnt Signaling in Cancer Stem Cell Biology

    PubMed Central

    de Sousa e Melo, Felipe; Vermeulen, Louis

    2016-01-01

    Aberrant regulation of Wnt signaling is a common theme seen across many tumor types. Decades of research have unraveled the epigenetic and genetic alterations that result in elevated Wnt pathway activity. More recently, it has become apparent that Wnt signaling levels identify stem-like tumor cells that are responsible for fueling tumor growth. As therapeutic targeting of these tumor stem cells is an intense area of investigation, a concise understanding on how Wnt activity relates to cancer stem cell traits is needed. This review attempts at summarizing the intricacies between Wnt signaling and cancer stem cell biology with a special emphasis on colorectal cancer. PMID:27355964

  17. Stomach development, stem cells and disease.

    PubMed

    Kim, Tae-Hee; Shivdasani, Ramesh A

    2016-02-15

    The stomach, an organ derived from foregut endoderm, secretes acid and enzymes and plays a key role in digestion. During development, mesenchymal-epithelial interactions drive stomach specification, patterning, differentiation and growth through selected signaling pathways and transcription factors. After birth, the gastric epithelium is maintained by the activity of stem cells. Developmental signals are aberrantly activated and stem cell functions are disrupted in gastric cancer and other disorders. Therefore, a better understanding of stomach development and stem cells can inform approaches to treating these conditions. This Review highlights the molecular mechanisms of stomach development and discusses recent findings regarding stomach stem cells and organoid cultures, and their roles in investigating disease mechanisms.

  18. Spheroid body-forming cells in the human gastric cancer cell line MKN-45 possess cancer stem cell properties.

    PubMed

    Liu, Jianming; Ma, Lilin; Xu, Junfei; Liu, Chun; Zhang, Jianguo; Liu, Jie; Chen, Ruixin; Zhou, Youlang

    2013-02-01

    The cancer stem cell theory hypothesizes that cancer stem cells (CSCs), which possess self-renewal and other stem cell properties, are regarded as the cause of tumor formation, recurrence and metastasis. The isolation and identification of CSCs could help to develop novel therapeutic strategies specifically targeting CSCs. In this study, we enriched gastric cancer stem cells through spheroid body formation by cultivating the human gastric cancer cell line MKN-45 in defined serum-free medium. The stemness characteristics of spheroid body-forming cells, including self-renewal, proliferation, chemoresistance, tumorigenicity of the MKN-45 spheroid body-forming cells were evaluated, and the expression levels of stemness genes and related proteins in the MKN-45 spheroid body-forming cells were assessed. Furthermore, immunofluorescence staining for the stem cell markers on spheroid body-forming cells was examined to evaluate the association between stemness factors (Oct4, Sox2, Nanog) and the proposed CSC marker CD44. Our data demonstrated that non-adherent spheroid body-forming cells from the gastric cancer cell line MKN-45 cultured in stem cell-conditioned medium possessed gastric CSC properties, such as persistent self-renewal, extensive proliferation, drug resistance, high tumorigenic capacity and overexpression of CSC-related genes and proteins (Oct4, Sox2, Nanog and CD44), compared with the parental cells. More importantly, CD44-positive cells co-expressing the pluripotency genes Oct4, Sox2 and Nanog may represent gastric CSCs. Further experiments using more refined selection criteria such as a combination of two or multiple markers would be useful to specifically identify and purify CSCs.

  19. [Stem cells - biology and therapeutic application].

    PubMed

    Sikora, Magdalena A; Olszewski, Waldemar L

    2004-04-01

    Enormous hope is connected with stem cells with regard to cell therapy, and this has become one of the most dynamically developing areas of science at the moment. A stem cell has unlimited potential for self-renewal. It appears that it can be a source of in vitro differentiated progeny cells capable of repairing damaged tissue. These review provides information about the biological properties of embryonic stem cells, i.e. ESs (embryonic stem cells), EGs (embryonic germ cells), and ECs (embryonic carcinoma cells). Possible human embryonic stem cell applications are described, with consideration of the desired cell line and the signals involved in their differentiation. The information about adult stem cells present - hemopoietic stem cells and the cells residing in selected tissues and organs: endothelium, pancreas, liver, epithelium, and gastrointestinal tract. Methods of their identification using the cell surfaces are also presented: the possibilities of in vitro transdifferentation, the phenomenon of in vivo plasticity, as well as morphological and genetic properties. Some topics of cell therapy and its clinical application in diabetics amplification are included. PMID:15114255

  20. Cancer stem cells: impact, heterogeneity, and uncertainty

    PubMed Central

    Magee, Jeffrey A.; Piskounova, Elena; Morrison, Sean J.

    2015-01-01

    The differentiation of tumorigenic cancer stem cells into non-tumorigenic cancer cells confers heterogeneity to some cancers beyond that explained by clonal evolution or environmental differences. In such cancers, functional differences between tumorigenic and non-tumorigenic cells influence response to therapy and prognosis. However, it remains uncertain whether the model applies to many, or few, cancers due to questions about the robustness of cancer stem cell markers and the extent to which existing assays underestimate the frequency of tumorigenic cells. In cancers with rapid genetic change, reversible changes in cell states, or biological variability among patients the stem cell model may not be readily testable. PMID:22439924

  1. Single-cell sequencing in stem cell biology.

    PubMed

    Wen, Lu; Tang, Fuchou

    2016-04-15

    Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

  2. Current Biosafety Considerations in Stem Cell Therapy.

    PubMed

    Mousavinejad, Masoumeh; Andrews, Peter W; Shoraki, Elham Kargar

    2016-01-01

    Stem cells can be valuable model systems for drug discovery and modelling human diseases as well as to investigate cellular interactions and molecular events in the early stages of development. Controlling the differentiation of stem cells into specific germ layers provides a potential source of highly specialized cells for therapeutic applications. In recent years, finding individual properties of stem cells such as their ultimate self-renewal capacity and the generation of particular cell lines by differentiation under specific culture conditions underpins the development of regenerative therapies. These futures make stem cells a leading candidate to treat a wide range of diseases. Nevertheless, as with all novel treatments, safety issues are one of the barriers that should be overcome to guarantee the quality of a patient's life after stem cell therapy. Many studies have pointed to a large gap in our knowledge about the therapeutic applications of these cells. This gap clearly shows the importance of biosafety concerns for the current status of cell-based therapies, even more than their therapeutic efficacy. Currently, scientists report that tumorigenicity and immunogenicity are the two most important associated cell-based therapy risks. In principle, intrinsic factors such as cell characteristics and extrinsic elements introduced by manufacturing of stem cells can result in tumor formation and immunological reactions after stem cell transplantation. Therapeutic research shows there are many biological questions regarding safety issues of stem cell clinical applications. Stem cell therapy is a rapidly advancing field that needs to focus more on finding a comprehensive technology for assessing risk. A variety of risk factors (from intrinsic to extrinsic) should be considered for safe clinical stem cell therapies. PMID:27540533

  3. Current Biosafety Considerations in Stem Cell Therapy

    PubMed Central

    Mousavinejad, Masoumeh; Andrews, Peter W.; Shoraki, Elham Kargar

    2016-01-01

    Stem cells can be valuable model systems for drug discovery and modelling human diseases as well as to investigate cellular interactions and molecular events in the early stages of development. Controlling the differentiation of stem cells into specific germ layers provides a potential source of highly specialized cells for therapeutic applications. In recent years, finding individual properties of stem cells such as their ultimate self-renewal capacity and the generation of particular cell lines by differentiation under specific culture conditions underpins the development of regenerative therapies. These futures make stem cells a leading candidate to treat a wide range of diseases. Nevertheless, as with all novel treatments, safety issues are one of the barriers that should be overcome to guarantee the quality of a patient’s life after stem cell therapy. Many studies have pointed to a large gap in our knowledge about the therapeutic applications of these cells. This gap clearly shows the importance of biosafety concerns for the current status of cell-based therapies, even more than their therapeutic efficacy. Currently, scientists report that tumorigenicity and immunogenicity are the two most important associated cell-based therapy risks. In principle, intrinsic factors such as cell characteristics and extrinsic elements introduced by manufacturing of stem cells can result in tumor formation and immunological reactions after stem cell transplantation. Therapeutic research shows there are many biological questions regarding safety issues of stem cell clinical applications. Stem cell therapy is a rapidly advancing field that needs to focus more on finding a comprehensive technology for assessing risk. A variety of risk factors (from intrinsic to extrinsic) should be considered for safe clinical stem cell therapies. PMID:27540533

  4. Strategies to improve homing of mesenchymal stem cells for greater efficacy in stem cell therapy.

    PubMed

    Naderi-Meshkin, Hojjat; Bahrami, Ahmad Reza; Bidkhori, Hamid Reza; Mirahmadi, Mahdi; Ahmadiankia, Naghmeh

    2015-01-01

    Stem/progenitor cell-based therapeutic approach in clinical practice has been an elusive dream in medical sciences, and improvement of stem cell homing is one of major challenges in cell therapy programs. Stem/progenitor cells have a homing response to injured tissues/organs, mediated by interactions of chemokine receptors expressed on the cells and chemokines secreted by the injured tissue. For improvement of directed homing of the cells, many techniques have been developed either to engineer stem/progenitor cells with higher amount of chemokine receptors (stem cell-based strategies) or to modulate the target tissues to release higher level of the corresponding chemokines (target tissue-based strategies). This review discusses both of these strategies involved in the improvement of stem cell homing focusing on mesenchymal stem cells as most frequent studied model in cellular therapies.

  5. In search of liver cancer stem cells.

    PubMed

    Ma, Stephanie; Chan, Kwok Wah; Guan, Xin-Yuan

    2008-09-01

    Recent research efforts in stem cell and cancer biology have put forth a "stem cell model of carcinogenesis" which stipulates that the capability to maintain tumor formation and growth specifically resides in a small population of cells called cancer stem cells. The stem cell-like characteristics of these cells, including their ability to self-renew and differentiate; and their limited number within the bulk of the tumor mass, are believed to account for their capability to escape conventional therapies. In the past few years, the hypothesis of stem cell-driven tumorigenesis in liver cancer has received substantial support from the recent ability to identify and isolate a subpopulation of liver cancer cells that is not only able to initiate tumor growth, but also serially establish themselves as tumor xenografts with high efficiency and consistency. In this review, stem cell biology that contributes to explain tumor development in the particular context of liver cancer will be discussed. We will begin by briefly considering the knowledge available on normal liver stem cells and their role in tissue renewal and regeneration. We will then summarize the current scientific knowledge of liver cancer stem cells, discuss their relevance to the diagnosis and treatment of the disease and consider the outstanding challenges and potential opportunities that lie ahead of us.

  6. Stem cells in bone tissue engineering.

    PubMed

    Seong, Jeong Min; Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Mantalaris, Anathathios; Hwang, Yu-Shik

    2010-12-01

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone.

  7. Generation of new islets from stem cells.

    PubMed

    Roche, Enrique; Soria, Bernat

    2004-01-01

    Spain ranks number one in organ donors (35 per million per yr). Although the prevalence of diabetes is low (100,000 type 1 diabetic patients and 2 million type 2 diabetic patients), the expected number of patients receiving islet transplants should be estimated at 200 per year. Islet replacement represents a promising cure for diabetes and has been successfully applied in a limited number of type 1 diabetic patients, resulting in insulin independence for periods longer than 3 yr. However, it has been difficult to obtain sufficient numbers of islets from cadaveric donors. Interesting alternatives include acquiring renewable sources of cells using either embryonic or adult stem cells to overcome the islet scarcity problem. Stem cells are capable of extensive proliferation rates and are capable of differentiating into other cell types of the body. In particular, totipotent stem cells are capable of differentiating into all cell types in the body, whereas pluripotent stem cells are limited to the development of a certain number of differentiated cell types. Insulin-producing cells have been obtained from both embryonic and adult stem cells using several approaches. In animal models of diabetes, the therapeutic application of bioengineered insulin-secreting cells derived from stem cells has delivered promising results. This review will summarize the different approaches that have been used to obtain insulin-producing cells from embryonic and adult stem cells and highlights the key points that will allow in vitro differentiation and subsequent transplantation in the future. PMID:15289648

  8. HMGA1 silencing restores normal stem cell characteristics in colon cancer stem cells by increasing p53 levels

    PubMed Central

    Puca, Francesca; Colamaio, Marianna; Federico, Antonella; Gemei, Marica; Tosti, Nadia; Bastos, André Uchimura; Vecchio, Luigi Del; Pece, Salvatore; Battista, Sabrina; Fusco, Alfredo

    2014-01-01

    High-mobility group A1 (HMGA1) proteins are architectural chromatinic proteins, abundantly expressed during embryogenesis and in most cancer tissues, but expressed at low levels or absent in normal adult tissues. Several studies have demonstrated that HMGA1 proteins play a causal role in neoplastic cell transformation. The aim of this study was to investigate the role of these proteins in the control of cancer stem cells (CSCs), which have emerged as a preferred target in cancer therapy, because of their role in cancer recurrence. We observed that HMGA1 is overexpressed in colon tumour stem cell (CTSC) lines compared to normal and colon cancer tissues. We demonstrated that HMGA1 silencing in CTSCs increases stem cell quiescence and reduces self-renewal and sphere-forming efficiency (SFE). The latter, together with the upregulation and asymmetric distribution of NUMB, is indicative of the recovery of an asymmetric division pattern, typical of normal stem cells. We further found that HMGA1 transcriptionally regulates p53, which is known to control the balance between symmetric and asymmetric divisions in CSCs. Therefore, our data indicate a critical role for HMGA1 in regulating both self-renewal and the symmetric/asymmetric division ratio in CSCs, suggesting that blocking HMGA1 function may be an effective anti-cancer therapy. PMID:24833610

  9. Adult stem-like cells in kidney

    PubMed Central

    Hishikawa, Keiichi; Takase, Osamu; Yoshikawa, Masahiro; Tsujimura, Taro; Nangaku, Masaomi; Takato, Tsuyoshi

    2015-01-01

    Human pluripotent cells are promising for treatment for kidney diseases, but the protocols for derivation of kidney cell types are still controversial. Kidney tissue regeneration is well confirmed in several lower vertebrates such as fish, and the repair of nephrons after tubular damages is commonly observed after renal injury. Even in adult mammal kidney, renal progenitor cell or system is reportedly presents suggesting that adult stem-like cells in kidney can be practical clinical targets for kidney diseases. However, it is still unclear if kidney stem cells or stem-like cells exist or not. In general, stemness is defined by several factors such as self-renewal capacity, multi-lineage potency and characteristic gene expression profiles. The definite use of stemness may be obstacle to understand kidney regeneration, and here we describe the recent broad findings of kidney regeneration and the cells that contribute regeneration. PMID:25815133

  10. Nonclinical safety strategies for stem cell therapies

    SciTech Connect

    Sharpe, Michaela E.; Morton, Daniel; Rossi, Annamaria

    2012-08-01

    Recent breakthroughs in stem cell biology, especially the development of the induced pluripotent stem cell techniques, have generated tremendous enthusiasm and efforts to explore the therapeutic potential of stem cells in regenerative medicine. Stem cell therapies are being considered for the treatment of degenerative diseases, inflammatory conditions, cancer and repair of damaged tissue. The safety of a stem cell therapy depends on many factors including the type of cell therapy, the differentiation status and proliferation capacity of the cells, the route of administration, the intended clinical location, long term survival of the product and/or engraftment, the need for repeated administration, the disease to be treated and the age of the population. Understanding the product profile of the intended therapy is crucial to the development of the nonclinical safety study design.

  11. Adult stem-like cells in kidney.

    PubMed

    Hishikawa, Keiichi; Takase, Osamu; Yoshikawa, Masahiro; Tsujimura, Taro; Nangaku, Masaomi; Takato, Tsuyoshi

    2015-03-26

    Human pluripotent cells are promising for treatment for kidney diseases, but the protocols for derivation of kidney cell types are still controversial. Kidney tissue regeneration is well confirmed in several lower vertebrates such as fish, and the repair of nephrons after tubular damages is commonly observed after renal injury. Even in adult mammal kidney, renal progenitor cell or system is reportedly presents suggesting that adult stem-like cells in kidney can be practical clinical targets for kidney diseases. However, it is still unclear if kidney stem cells or stem-like cells exist or not. In general, stemness is defined by several factors such as self-renewal capacity, multi-lineage potency and characteristic gene expression profiles. The definite use of stemness may be obstacle to understand kidney regeneration, and here we describe the recent broad findings of kidney regeneration and the cells that contribute regeneration. PMID:25815133

  12. Cancer stem cells in glioblastoma

    PubMed Central

    Lathia, Justin D.; Mack, Stephen C.; Mulkearns-Hubert, Erin E.; Valentim, Claudia L.L.; Rich, Jeremy N.

    2015-01-01

    Tissues with defined cellular hierarchies in development and homeostasis give rise to tumors with cellular hierarchies, suggesting that tumors recapitulate specific tissues and mimic their origins. Glioblastoma (GBM) is the most prevalent and malignant primary brain tumor and contains self-renewing, tumorigenic cancer stem cells (CSCs) that contribute to tumor initiation and therapeutic resistance. As normal stem and progenitor cells participate in tissue development and repair, these developmental programs re-emerge in CSCs to support the development and progressive growth of tumors. Elucidation of the molecular mechanisms that govern CSCs has informed the development of novel targeted therapeutics for GBM and other brain cancers. CSCs are not self-autonomous units; rather, they function within an ecological system, both actively remodeling the microenvironment and receiving critical maintenance cues from their niches. To fulfill the future goal of developing novel therapies to collapse CSC dynamics, drawing parallels to other normal and pathological states that are highly interactive with their microenvironments and that use developmental signaling pathways will be beneficial. PMID:26109046

  13. Neurogenic differentiation of amniotic fluid stem cells.

    PubMed

    Rosner, M; Mikula, M; Preitschopf, A; Feichtinger, M; Schipany, K; Hengstschläger, M

    2012-05-01

    In 2003, human amniotic fluid has been shown to contain stem cells expressing Oct-4, a marker for pluripotency. This finding initiated a rapidly growing and very promising new stem cell research field. Since then, amniotic fluid stem (AFS) cells have been demonstrated to harbour the potential to differentiate into any of the three germ layers and to form three-dimensional aggregates, so-called embryoid bodies, known as the principal step in the differentiation of pluripotent stem cells. Marker selection and minimal dilution approaches allow the establishment of monoclonal AFS cell lineages with high proliferation potential. AFS cells have a lower risk for tumour development and do not raise the ethical issues of embryonic stem cells. Compared to induced pluripotent stem cells, AFS cells do not need exogenic treatment to induce pluripotency, are chromosomal stable and do not harbour the epigenetic memory and accumulated somatic mutations of specific differentiated source cells. Compared to adult stem cells, AFS can be grown in larger quantities and show higher differentiation potential. Accordingly, in the recent past, AFS became increasingly accepted as an optimal tool for basic research and probably also for specific cell-based therapies. Here, we review the current knowledge on the neurogenic differentiation potential of AFS cells.

  14. Prostate cancer stem cell biology

    PubMed Central

    Yu, Chunyan; Yao, Zhi; Jiang, Yuan; Keller, Evan. T.

    2012-01-01

    The cancer stem cell (CSC) model provides insights into pathophysiology of cancers and their therapeutic response. The CSC model has been both controversial, yet provides a foundation to explore cancer biology. In this review, we provide an overview of CSC concepts, biology and potential therapeutic avenues. We then focus on prostate CSC including (1) their purported origin as either basal-derived or luminal-derived cells; (2) markers used for prostate CSC identification; (3) alterations of signaling pathways in prostate CSCs (4) involvement of prostate CSCs in metastasis of PCa and (5) microRNA-mediated regulation of prostate CSCs. Although definitive evidence for the identification and characterization of prostate CSCs still remains unclear, future directions pursuing therapeutic targets of CSCs may provide novel insights for the treatment of PCa. PMID:22402315

  15. Glial cell derived neurotrophic factor induces spermatogonial stem cell marker genes in chicken mesenchymal stem cells.

    PubMed

    Boozarpour, Sohrab; Matin, Maryam M; Momeni-Moghaddam, Madjid; Dehghani, Hesam; Mahdavi-Shahri, Naser; Sisakhtnezhad, Sajjad; Heirani-Tabasi, Asieh; Irfan-Maqsood, Muhammad; Bahrami, Ahmad Reza

    2016-06-01

    Mesenchymal stem cells (MSCs) are known with the potential of multi-lineage differentiation. Advances in differentiation technology have also resulted in the conversion of MSCs to other kinds of stem cells. MSCs are considered as a suitable source of cells for biotechnology purposes because they are abundant, easily accessible and well characterized cells. Nowadays small molecules are introduced as novel and efficient factors to differentiate stem cells. In this work, we examined the potential of glial cell derived neurotrophic factor (GDNF) for differentiating chicken MSCs toward spermatogonial stem cells. MSCs were isolated and characterized from chicken and cultured under treatment with all-trans retinoic acid (RA) or glial cell derived neurotrophic factor. Expression analysis of specific genes after 7days of RA treatment, as examined by RT-PCR, proved positive for some germ cell markers such as CVH, STRA8, PLZF and some genes involved in spermatogonial stem cell maintenance like BCL6b and c-KIT. On the other hand, GDNF could additionally induce expression of POU5F1, and NANOG as well as other genes which were induced after RA treatment. These data illustrated that GDNF is relatively more effective in diverting chicken MSCs towards Spermatogonial stem cell -like cells in chickens and suggests GDNF as a new agent to obtain transgenic poultry, nevertheless, exploitability of these cells should be verified by more experiments. PMID:27026484

  16. Glial cell derived neurotrophic factor induces spermatogonial stem cell marker genes in chicken mesenchymal stem cells.

    PubMed

    Boozarpour, Sohrab; Matin, Maryam M; Momeni-Moghaddam, Madjid; Dehghani, Hesam; Mahdavi-Shahri, Naser; Sisakhtnezhad, Sajjad; Heirani-Tabasi, Asieh; Irfan-Maqsood, Muhammad; Bahrami, Ahmad Reza

    2016-06-01

    Mesenchymal stem cells (MSCs) are known with the potential of multi-lineage differentiation. Advances in differentiation technology have also resulted in the conversion of MSCs to other kinds of stem cells. MSCs are considered as a suitable source of cells for biotechnology purposes because they are abundant, easily accessible and well characterized cells. Nowadays small molecules are introduced as novel and efficient factors to differentiate stem cells. In this work, we examined the potential of glial cell derived neurotrophic factor (GDNF) for differentiating chicken MSCs toward spermatogonial stem cells. MSCs were isolated and characterized from chicken and cultured under treatment with all-trans retinoic acid (RA) or glial cell derived neurotrophic factor. Expression analysis of specific genes after 7days of RA treatment, as examined by RT-PCR, proved positive for some germ cell markers such as CVH, STRA8, PLZF and some genes involved in spermatogonial stem cell maintenance like BCL6b and c-KIT. On the other hand, GDNF could additionally induce expression of POU5F1, and NANOG as well as other genes which were induced after RA treatment. These data illustrated that GDNF is relatively more effective in diverting chicken MSCs towards Spermatogonial stem cell -like cells in chickens and suggests GDNF as a new agent to obtain transgenic poultry, nevertheless, exploitability of these cells should be verified by more experiments.

  17. Enhancing spontaneous stem cell healing (Review)

    PubMed Central

    MAGUIRE, GREG; FRIEDMAN, PETER

    2014-01-01

    Adult stem cells are distributed throughout the human body and are responsible to a great extent for the body’s ability to maintain and heal itself. Accumulating data since the 1990s regarding stem cells have demonstrated that the beneficial effects of stem cells are not restricted to their ability to differentiate and are more likely due to their ability to release a multitude of molecules. Recent studies indicated that ≤80% of the therapeutic benefit of adult stem cells is manifested by the stem cell released molecules (SRM) rather than the differentiation of the stem cells into mature tissue. Stem cells may release potent combinations of factors that modulate the molecular composition of the cellular milieu to evoke a multitude of responses from neighboring cells. A multitude of pathways are involved in cellular and tissue function and, when the body is in a state of disease or trauma, a multitude of pathways are involved in the underlying mechanisms of that disease or trauma. Therefore, stem cells represent a natural systems-based biological factory for the production and release of a multitude of molecules that interact with the system of biomolecular circuits underlying disease or tissue damage. Currently, efforts are aimed at defining, stimulating, enhancing and harnessing SRM mechanisms, in order to develop systems-based methods for tissue regeneration, develop drugs/biologics or other therapeutics and enhance the release of SRM into the body for natural healing through proper dietary, exercise and other lifestyle strategies. PMID:24649089

  18. DNA damage response in adult stem cells.

    PubMed

    Insinga, Alessandra; Cicalese, Angelo; Pelicci, Pier Giuseppe

    2014-04-01

    This review discusses the processes of DNA-damage-response and DNA-damage repair in stem and progenitor cells of several tissues. The long life-span of stem cells suggests that they may respond differently to DNA damage than their downstream progeny and, indeed, studies have begun to elucidate the unique stem cell response mechanisms to DNA damage. Because the DNA damage responses in stem cells and progenitor cells are distinctly different, stem and progenitor cells should be considered as two different entities from this point of view. Hematopoietic and mammary stem cells display a unique DNA-damage response, which involves active inhibition of apoptosis, entry into the cell-cycle, symmetric division, partial DNA repair and maintenance of self-renewal. Each of these biological events depends on the up-regulation of the cell-cycle inhibitor p21. Moreover, inhibition of apoptosis and symmetric stem cell division are the consequence of the down-regulation of the tumor suppressor p53, as a direct result of p21 up-regulation. A deeper understanding of these processes is required before these findings can be translated into human anti-aging and anti-cancer therapies. One needs to clarify and dissect the pathways that control p21 regulation in normal and cancer stem cells and define (a) how p21 blocks p53 functions in stem cells and (b) how p21 promotes DNA repair in stem cells. Is this effect dependent on p21s ability to inhibit p53? Such molecular knowledge may pave the way to methods for maintaining short-term tissue reconstitution while retaining long-term cellular and genomic integrity.

  19. Stem cells of the skin epithelium

    PubMed Central

    Alonso, Laura; Fuchs, Elaine

    2003-01-01

    Tissue stem cells form the cellular base for organ homeostasis and repair. Stem cells have the unusual ability to renew themselves over the lifetime of the organ while producing daughter cells that differentiate into one or multiple lineages. Difficult to identify and characterize in any tissue, these cells are nonetheless hotly pursued because they hold the potential promise of therapeutic reprogramming to grow human tissue in vitro, for the treatment of human disease. The mammalian skin epithelium exhibits remarkable turnover, punctuated by periods of even more rapid production after injury due to burn or wounding. The stem cells responsible for supplying this tissue with cellular substrate are not yet easily distinguishable from neighboring cells. However, in recent years a significant body of work has begun to characterize the skin epithelial stem cells, both in tissue culture and in mouse and human skin. Some epithelial cells cultured from skin exhibit prodigious proliferative potential; in fact, for >20 years now, cultured human skin has been used as a source of new skin to engraft onto damaged areas of burn patients, representing one of the first therapeutic uses of stem cells. Cell fate choices, including both self-renewal and differentiation, are crucial biological features of stem cells that are still poorly understood. Skin epithelial stem cells represent a ripe target for research into the fundamental mechanisms underlying these important processes. PMID:12913119

  20. Hyaluronan synthase 3 (HAS3) overexpression downregulates MV3 melanoma cell proliferation, migration and adhesion

    SciTech Connect

    Takabe, Piia; Bart, Geneviève; Ropponen, Antti; Rilla, Kirsi; Tammi, Markku; Tammi, Raija; Pasonen-Seppänen, Sanna

    2015-09-10

    Malignant skin melanoma is one of the most deadly human cancers. Extracellular matrix (ECM) influences the growth of malignant tumors by modulating tumor cells adhesion and migration. Hyaluronan is an essential component of the ECM, and its amount is altered in many tumors, suggesting an important role for hyaluronan in tumorigenesis. Nonetheless its role in melanomagenesis is not understood. In this study we produced a MV3 melanoma cell line with inducible expression of the hyaluronan synthase 3 (HAS3) and studied its effect on the behavior of the melanoma cells. HAS3 overexpression expanded the cell surface hyaluronan coat and decreased melanoma cell adhesion, migration and proliferation by cell cycle arrest at G1/G0. Melanoma cell migration was restored by removal of cell surface hyaluronan by Streptomyces hyaluronidase and by receptor blocking with hyaluronan oligosaccharides, while the effect on cell proliferation was receptor independent. Overexpression of HAS3 decreased ERK1/2 phosphorylation suggesting that inhibition of MAP-kinase signaling was responsible for these suppressive effects on the malignant phenotype of MV3 melanoma cells. - Highlights: • Inducible HAS3-MV3 melanoma cell line was generated using Lentiviral transduction. • HAS3 overexpression inhibits MV3 cell migration via hyaluronan–receptor interaction. • HAS3 overexpression decreases MV3 melanoma cell proliferation and adhesion. • ERK1/2 phosphorylation is downregulated by 50% in HAS3 overexpressing cells. • The results suggest that hyaluronan has anti-cancer like effects in melanoma.

  1. Epidermal Stem Cells in Orthopaedic Regenerative Medicine

    PubMed Central

    Li, Jin; Zhen, Gehua; Tsai, Shin-Yi; Jia, Xiaofeng

    2013-01-01

    In the last decade, great advances have been made in epidermal stem cell studies at the cellular and molecular level. These studies reported various subpopulations and differentiations existing in the epidermal stem cell. Although controversies and unknown issues remain, epidermal stem cells possess an immune-privileged property in transplantation together with easy accessibility, which is favorable for future clinical application. In this review, we will summarize the biological characteristics of epidermal stem cells, and their potential in orthopedic regenerative medicine. Epidermal stem cells play a critical role via cell replacement, and demonstrate significant translational potential in the treatment of orthopedic injuries and diseases, including treatment for wound healing, peripheral nerve and spinal cord injury, and even muscle and bone remodeling. PMID:23727934

  2. Transdifferentiation of Stem Cells: A Critical View

    NASA Astrophysics Data System (ADS)

    Gruh, Ina; Martin, Ulrich

    Recently a large amount of new data on the plasticity of stem cells of various lineages have emerged, providing new perspectives especially for the therapeutic application of adult stem cells. Previously unknown possibilities of cell differentiation beyond the known commitment of a given stem cell have been described using keywords such as "blood to liver," or "bone to brain." Controversies on the likelihood, as well as the biological significance, of these conversions almost immediately arose within this young field of stem cell biology. This chapter will concentrate on these controversies and focus on selected examples demonstrating the technical aspects of stem cell transdifferentiation and the evaluation of the tools used to analyze these events.

  3. Cancer stem cells of the digestive system.

    PubMed

    Colvin, Hugh S; Nishida, Naohiro; Koseki, Jun; Konno, Masamitsu; Kawamoto, Koichi; Tsunekuni, Kenta; Doki, Yuichiro; Mori, Masaki; Ishii, Hideshi

    2014-12-01

    Stem cells of the digestive system are ideal in many ways for research, given they are abundant, highly proliferative and have a uniform structural arrangement. This in turn has enormously aided the research of cancer stem cells of the digestive system, which is now shaping our understanding of cancer stem cells. In this review, the recent advances in the understanding of cancer stem cells of the digestive system have been summarized, including aspects such as their identification, origin, cell-cycle dormancy, relationship with epithelial-mesenchymal transition, cellular metabolism and the underlying molecular mechanisms. Newly acquired knowledge concerning cancer stem cells have led to the development of novel cancer therapeutics with provisional yet encouraging results.

  4. Signaling involved in stem cell reprogramming and differentiation

    PubMed Central

    Tanabe, Shihori

    2015-01-01

    Stem cell differentiation is regulated by multiple signaling events. Recent technical advances have revealed that differentiated cells can be reprogrammed into stem cells. The signals involved in stem cell programming are of major interest in stem cell research. The signaling mechanisms involved in regulating stem cell reprogramming and differentiation are the subject of intense study in the field of life sciences. In this review, the molecular interactions and signaling pathways related to stem cell differentiation are discussed. PMID:26328015

  5. Clonogenicity: holoclones and meroclones contain stem cells.

    PubMed

    Beaver, Charlotte M; Ahmed, Aamir; Masters, John R

    2014-01-01

    When primary cultures of normal cells are cloned, three types of colony grow, called holoclones, meroclones and paraclones. These colonies are believed to be derived from stem cells, transit-amplifying cells and differentiated cells respectively. More recently, this approach has been extended to cancer cell lines. However, we observed that meroclones from the prostate cancer cell line DU145 produce holoclones, a paradoxical observation as meroclones are thought to be derived from transit-amplifying cells. The purpose of this study was to confirm this observation and determine if both holoclones and meroclones from cancer cell lines contain stem cells. We demonstrated that both holoclones and meroclones can be serially passaged indefinitely, are highly proliferative, can self-renew to form spheres, are serially tumorigenic and express stem cell markers. This study demonstrates that the major difference between holoclones and meroclones derived from a cancer cell line is the proportion of stem cells within each colony, not the presence or absence of stem cells. These findings may reflect the properties of cancer as opposed to normal cells, perhaps indicating that the hierarchy of stem cells is more extensive in cancer.

  6. Overexpression of glial cell line-derived neurotrophic factor induces genes regulating migration and differentiation of neuronal progenitor cells.

    PubMed

    Pahnke, Jens; Mix, Eilhard; Knoblich, Rupert; Müller, Jana; Zschiesche, Marlies; Schubert, Beke; Koczan, Dirk; Bauer, Peter; Böttcher, Tobias; Thiesen, Hans-Jürgen; Lazarov, Ludmil; Wree, Andreas; Rolfs, Arndt

    2004-07-15

    The glial cell line-derived neurotrophic factor (GDNF) is involved in the development and maintenance of neural tissues. Mutations in components of its signaling pathway lead to severe migration deficits of neuronal crest stem cells, tumor formation, or ablation of the urinary system. In animal models of Parkinson's disease, GDNF has been recognized to be neuroprotective and to improve motor function when delivered into the cerebral ventricles or into the substantia nigra. Here, we characterize the network of 43 genes induced by GDNF overproduction of neuronal progenitor cells (ST14A), which mainly regulate migration and differentiation of neuronal progenitor cells. GDNF down-regulates doublecortin, Paf-ah1b (Lis1), dynamin, and alpha-tubulin, which are involved in neocortical lamination and cytoskeletal reorganization. Axonal guidance depends on cell-surface molecules and extracellular matrix proteins. Laminin, Mpl3, Alcam, Bin1, Id1, Id2, Id3, neuregulin1, the ephrinB2-receptor, neuritin, focal adhesion kinase (FAK), Tc10, Pdpk1, clusterin, GTP-cyclooxygenase1, and follistatin are genes up-regulated by GDNF overexpression. Moreover, we found four key enzymes of the cholesterol-synthesis pathway to be down-regulated leading to decreased farnesyl-pyrophospate production. Many proteins are anchored by farnesyl-derivates at the cell membrane. The identification of these GDNF-regulated genes may open new opportunities for directly influencing differentiation and developmental processes of neurons. PMID:15212950

  7. Pathological modifications of plant stem cell destiny

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In higher plants, the shoot apex contains undifferentiated stem cells that give rise to various tissues and organs. The fate of these stem cells determines the pattern of plant growth as well as reproduction; and such fate is genetically preprogrammed. We found that a bacterial infection can derai...

  8. Skeletal stem cells in space and time.

    PubMed

    Kassem, Moustapha; Bianco, Paolo

    2015-01-15

    The nature, biological characteristics, and contribution to organ physiology of skeletal stem cells are not completely determined. Chan et al. and Worthley et al. demonstrate that a stem cell for skeletal tissues, and a system of more restricted, downstream progenitors, can be identified in mice and demonstrate its role in skeletal tissue maintenance and regeneration.

  9. Stem Cell Research and Health Education

    ERIC Educational Resources Information Center

    Eve, David J.; Marty, Phillip J.; McDermott, Robert J.; Klasko, Stephen K.; Sanberg, Paul R.

    2008-01-01

    Stem cells are being touted as the greatest discovery for the potential treatment of a myriad of diseases in the new millennium, but there is still much research to be done before it will be known whether they can live up to this description. There is also an ethical debate over the production of one of the most valuable types of stem cell: the…

  10. Improving Stem Cell Therapeutics with Mechanobiology.

    PubMed

    Shin, Jae-Won; Mooney, David J

    2016-01-01

    In recent years, it has become clear that mechanical cues play an integral role in maintaining stem cell functions. Here we discuss how integrating physical approaches and engineering principles in stem cell biology, including culture systems, preclinical models, and functional assessment, may improve clinical application in regenerative medicine.

  11. Stem Cell Fate Is a Touchy Subject.

    PubMed

    Smith, Quinton; Gerecht, Sharon

    2016-09-01

    Uncoupling synergistic interactions between physio-chemical cues that guide stem cell fate may improve efforts to direct their differentiation in culture. Using supramolecular hydrogels, Alakpa et al. (2016) demonstrate that mesenchymal stem cell differentiation is paired to depletion of bioactive metabolites, which can be utilized to chemically induce osteoblast and chondrocyte fate. PMID:27588745

  12. Engineering stem cells for future medicine.

    PubMed

    Ricotti, Leonardo; Menciassi, Arianna

    2013-03-01

    Despite their great potential in regenerative medicine applications, stem cells (especially pluripotent ones) currently show a limited clinical success, partly due to a lack of biological knowledge, but also due to a lack of specific and advanced technological instruments able to overcome the current boundaries of stem cell functional maturation and safe/effective therapeutic delivery. This paper aims at describing recent insights, current limitations, and future horizons related to therapeutic stem cells, by analyzing the potential of different bioengineering disciplines in bringing stem cells toward a safe clinical use. First, we clarify how and why stem cells should be properly engineered and which could be in a near future the challenges and the benefits connected with this process. Second, we identify different routes toward stem cell differentiation and functional maturation, relying on chemical, mechanical, topographical, and direct/indirect physical stimulation. Third, we highlight how multiscale modeling could strongly support and optimize stem cell engineering. Finally, we focus on future robotic tools that could provide an added value to the extent of translating basic biological knowledge into clinical applications, by developing ad hoc enabling technologies for stem cell delivery and control.

  13. Myofiber-specific TEAD1 overexpression drives satellite cell hyperplasia and counters pathological effects of dystrophin deficiency

    PubMed Central

    Southard, Sheryl; Kim, Ju-Ryoung; Low, SiewHui; Tsika, Richard W; Lepper, Christoph

    2016-01-01

    When unperturbed, somatic stem cells are poised to affect immediate tissue restoration upon trauma. Yet, little is known regarding the mechanistic basis controlling initial and homeostatic ‘scaling’ of stem cell pool sizes relative to their target tissues for effective regeneration. Here, we show that TEAD1-expressing skeletal muscle of transgenic mice features a dramatic hyperplasia of muscle stem cells (i.e. satellite cells, SCs) but surprisingly without affecting muscle tissue size. Super-numeral SCs attain a ‘normal’ quiescent state, accelerate regeneration, and maintain regenerative capacity over several injury-induced regeneration bouts. In dystrophic muscle, the TEAD1 transgene also ameliorated the pathology. We further demonstrate that hyperplastic SCs accumulate non-cell-autonomously via signal(s) from the TEAD1-expressing myofiber, suggesting that myofiber-specific TEAD1 overexpression activates a physiological signaling pathway(s) that determines initial and homeostatic SC pool size. We propose that TEAD1 and its downstream effectors are medically relevant targets for enhancing muscle regeneration and ameliorating muscle pathology. DOI: http://dx.doi.org/10.7554/eLife.15461.001 PMID:27725085

  14. Generation of functional thyroid from embryonic stem cells.

    PubMed

    Antonica, Francesco; Kasprzyk, Dominika Figini; Opitz, Robert; Iacovino, Michelina; Liao, Xiao-Hui; Dumitrescu, Alexandra Mihaela; Refetoff, Samuel; Peremans, Kathelijne; Manto, Mario; Kyba, Michael; Costagliola, Sabine

    2012-11-01

    The primary function of the thyroid gland is to metabolize iodide by synthesizing thyroid hormones, which are critical regulators of growth, development and metabolism in almost all tissues. So far, research on thyroid morphogenesis has been missing an efficient stem-cell model system that allows for the in vitro recapitulation of the molecular and morphogenic events regulating thyroid follicular-cell differentiation and subsequent assembly into functional thyroid follicles. Here we report that a transient overexpression of the transcription factors NKX2-1 and PAX8 is sufficient to direct mouse embryonic stem-cell differentiation into thyroid follicular cells that organize into three-dimensional follicular structures when treated with thyrotropin. These in vitro-derived follicles showed appreciable iodide organification activity. Importantly, when grafted in vivo into athyroid mice, these follicles rescued thyroid hormone plasma levels and promoted subsequent symptomatic recovery. Thus, mouse embryonic stem cells can be induced to differentiate into thyroid follicular cells in vitro and generate functional thyroid tissue.

  15. Inhibition of laminin-5 production in breast epithelial cells by overexpression of p300.

    PubMed

    Miller, K A; Chung, J; Lo, D; Jones, J C; Thimmapaya, B; Weitzman, S A

    2000-03-17

    The transcriptional coactivator p300 is essential for normal embryonic development and cellular differentiation. We have been studying the role of p300 in the transcription of a variety of genes, and we became interested in the role of this coactivator in the transcription of genes important in breast epithelial cell biology. From MCF-10A cells (spontaneously immortalized, nontransformed human breast epithelial cells), we developed cell lines that stably overexpress p300. These p300-overexpressing cells displayed reduced adhesion to culture dishes and were found to secrete an extracellular matrix deficient in laminin-5. Laminin-5 is the major extracellular matrix component produced by breast epithelium. Immunofluorescence studies, as well as experiments using normal matrix, confirmed that the decreased adhesion of p300-overexpressing cells is due to laminin-5-deficient extracellular matrix and not due to loss of laminin-5 receptors. Northern blots revealed markedly decreased levels of expression of two of the genes (designated LAMA3 and LAMC2) encoding the alpha3 and gamma2 chains of the laminin-5 heterotrimer in the cells that overexpress p300, whereas LAMB3 mRNA, encoding the third or beta3 chain of laminin-5, was not markedly reduced. Transient transfection experiments with a vector containing a murine LAMA3 promoter demonstrate that overexpressing p300 down-regulates the LAMA3 promoter. In summary, overexpression of p300 leads to down-regulation of laminin-5 production in breast epithelial cells, resulting in decreased adhesion. PMID:10713141

  16. Regulation of glycolysis by Pdk functions as a metabolic checkpoint for cell cycle quiescence in hematopoietic stem cells.

    PubMed

    Takubo, Keiyo; Nagamatsu, Go; Kobayashi, Chiharu I; Nakamura-Ishizu, Ayako; Kobayashi, Hiroshi; Ikeda, Eiji; Goda, Nobuhito; Rahimi, Yasmeen; Johnson, Randall S; Soga, Tomoyoshi; Hirao, Atsushi; Suematsu, Makoto; Suda, Toshio

    2013-01-01

    Defining the metabolic programs that underlie stem cell maintenance will be essential for developing strategies to manipulate stem cell capacity. Mammalian hematopoietic stem cells (HSCs) maintain cell cycle quiescence in a hypoxic microenvironment. It has been proposed that HSCs exhibit a distinct metabolic phenotype under these conditions. Here we directly investigated this idea using metabolomic analysis and found that HSCs generate adenosine-5'-triphosphate by anaerobic glycolysis through a pyruvate dehydrogenase kinase (Pdk)-dependent mechanism. Elevated Pdk expression leads to active suppression of the influx of glycolytic metabolites into mitochondria. Pdk overexpression in glycolysis-defective HSCs restored glycolysis, cell cycle quiescence, and stem cell capacity, while loss of both Pdk2 and Pdk4 attenuated HSC quiescence, glycolysis, and transplantation capacity. Moreover, treatment of HSCs with a Pdk mimetic promoted their survival and transplantation capacity. Thus, glycolytic metabolic status governed by Pdk acts as a cell cycle checkpoint that modulates HSC quiescence and function. PMID:23290136

  17. Comparison of American mink embryonic stem and induced pluripotent stem cell transcriptomes

    PubMed Central

    2015-01-01

    Background Recently fibroblasts of many mammalian species have been reprogrammed to pluripotent state using overexpression of several transcription factors. This technology allows production of induced pluripotent stem (iPS) cells with properties similar to embryonic stem (ES) cells. The completeness of reprogramming process is well studied in such species as mouse and human but there is not enough data on other species. We produced American mink (Neovison vison) ES and iPS cells and compared these cells using transcriptome analysis. Results We report the generation of 10 mink ES and 22 iPS cell lines. The majority of the analyzed cell lines had normal diploid chromosome number. The only ES cell line with XX chromosome set had both X-chromosomes in active state that is characteristic of pluripotent cells. The pluripotency of ES and iPS cell lines was confirmed by formation of teratomas with cell types representing all three germ layers. Transcriptome analysis of mink embryonic fibroblasts (EF), two ES and two iPS cell lines allowed us to identify 11831 assembled contigs which were annotated. These led to a number of 6891 unique genes. Of these 3201 were differentially expressed between mink EF and ES cells. We analyzed expression levels of these genes in iPS cell lines. This allowed us to show that 80% of genes were correctly reprogrammed in iPS cells, whereas approximately 6% had an intermediate expression pattern, about 7% were not reprogrammed and about 5% had a "novel" expression pattern. We observed expression of pluripotency marker genes such as Oct4, Sox2 and Rex1 in ES and iPS cell lines with notable exception of Nanog. Conclusions We had produced and characterized American mink ES and iPS cells. These cells were pluripotent by a number of criteria and iPS cells exhibited effective reprogramming. Interestingly, we had showed lack of Nanog expression and consider it as a species-specific feature. PMID:26694224

  18. Stem Cell Research: Unlocking the Mystery of Disease

    MedlinePlus

    ... Home Current Issue Past Issues From the Director: Stem Cell Research: Unlocking the Mystery of Disease Past Issues / Summer ... Zerhouni, NIH Director, described the need for expanding stem cell research. Recently, he spoke about stem cell research with ...

  19. Organ or Stem Cell Transplant and Your Mouth

    MedlinePlus

    ... Stem Cell Transplant and Your Mouth Organ or Stem Cell Transplant and Your Mouth Main Content Key Points​ ... Your Dentist Before Transplant Before an organ or stem cell transplant, have a dental checkup. Your mouth should ...

  20. Impact of retrotransposons in pluripotent stem cells.

    PubMed

    Tanaka, Yoshiaki; Chung, Leeyup; Park, In-Hyun

    2012-12-01

    Retrotransposons, which constitute approximately 40% of the human genome, have the capacity to 'jump' across the genome. Their mobility contributes to oncogenesis, evolution, and genomic plasticity of the host genome. Induced pluripotent stem cells as well as embryonic stem cells are more susceptible than differentiated cells to genomic aberrations including insertion, deletion and duplication. Recent studies have revealed specific behaviors of retrotransposons in pluripotent cells. Here, we review recent progress in understanding retrotransposons and provide a perspective on the relationship between retrotransposons and genomic variation in pluripotent stem cells. PMID:23135636

  1. STELLA Facilitates Differentiation of Germ Cell and Endodermal Lineages of Human Embryonic Stem Cells

    PubMed Central

    Wongtrakoongate, Patompon; Jones, Mark; Gokhale, Paul J.; Andrews, Peter W.

    2013-01-01

    Stella is a developmentally regulated gene highly expressed in mouse embryonic stem (ES) cells and in primordial germ cells (PGCs). In human, the gene encoding the STELLA homologue lies on chromosome 12p, which is frequently amplified in long-term cultured human ES cells. However, the role played by STELLA in human ES cells has not been reported. In the present study, we show that during retinoic acid (RA)-induced differentiation of human ES cells, expression of STELLA follows that of VASA, a marker of germline differentiation. By contrast, human embryonal carcinoma cells express STELLA at a higher level compared with both karyotypically normal and abnormal human ES cell lines. We found that over-expression of STELLA does not interfere with maintenance of the stem cell state of human ES cells, but following retinoic acid induction it leads to up-regulation of germline- and endodermal-associated genes, whereas neural markers PAX6 and NEUROD1 are down-regulated. Further, STELLA over-expression facilitates the differentiation of human ES cells into BE12-positive cells, in which the expression of germline- and endodermal-associated genes is enriched, and suppresses differentiation of the neural lineage. Taken together, this finding suggests a role for STELLA in facilitating germline and endodermal differentiation of human ES cells. PMID:23457636

  2. Artificial gametes from stem cells

    PubMed Central

    Moreno, Inmaculada; Míguez-Forjan, Jose Manuel

    2015-01-01

    The generation of artificial gametes is a real challenge for the scientific community today. In vitro development of human eggs and sperm will pave the way for the understanding of the complex process of human gametogenesis and will provide with human gametes for the study of infertility and the onset of some inherited disorders. However, the great promise of artificial gametes resides in their future application on reproductive treatments for all these people wishing to have genetically related children and for which gamete donation is now their unique option of parenthood. This is the case of infertile patients devoid of suitable gametes, same sex couples, singles and those fertile couples in a high risk of transmitting serious diseases to their progeny. In the search of the best method to obtain artificial gametes, many researchers have successfully obtained human germ cell-like cells from stem cells at different stages of differentiation. In the near future, this field will evolve to new methods providing not only viable but also functional and safe artificial germ cells. These artificial sperm and eggs should be able to recapitulate all the genetic and epigenetic processes needed for the correct gametogenesis, fertilization and embryogenesis leading to the birth of a healthy and fertile newborn. PMID:26161331

  3. Overcoming Multidrug Resistance in Cancer Stem Cells

    PubMed Central

    Moitra, Karobi

    2015-01-01

    The principle mechanism of protection of stem cells is through the expression of ATP-binding cassette (ABC) transporters. These transporters serve as the guardians of the stem cell population in the body. Unfortunately these very same ABC efflux pumps afford protection to cancer stem cells in tumors, shielding them from the adverse effects of chemotherapy. A number of strategies to circumvent the function of these transporters in cancer stem cells are currently under investigation. These strategies include the development of competitive and allosteric modulators, nanoparticle mediated delivery of inhibitors, targeted transcriptional regulation of ABC transporters, miRNA mediated inhibition, and targeting of signaling pathways that modulate ABC transporters. The role of ABC transporters in cancer stem cells will be explored in this paper and strategies aimed at overcoming drug resistance caused by these particular transporters will also be discussed. PMID:26649310

  4. Biophysical regulation of stem cell differentiation.

    PubMed

    Govey, Peter M; Loiselle, Alayna E; Donahue, Henry J

    2013-06-01

    Bone adaptation to its mechanical environment, from embryonic through adult life, is thought to be the product of increased osteoblastic differentiation from mesenchymal stem cells. In parallel with tissue-scale loading, these heterogeneous populations of multipotent stem cells are subject to a variety of biophysical cues within their native microenvironments. Bone marrow-derived mesenchymal stem cells-the most broadly studied source of osteoblastic progenitors-undergo osteoblastic differentiation in vitro in response to biophysical signals, including hydrostatic pressure, fluid flow and accompanying shear stress, substrate strain and stiffness, substrate topography, and electromagnetic fields. Furthermore, stem cells may be subject to indirect regulation by mechano-sensing osteocytes positioned to more readily detect these same loading-induced signals within the bone matrix. Such paracrine and juxtacrine regulation of differentiation by osteocytes occurs in vitro. Further studies are needed to confirm both direct and indirect mechanisms of biophysical regulation within the in vivo stem cell niche.

  5. [Stem cells--cloning, plasticity, bioethic].

    PubMed

    Pflegerl, Pamina; Keller, Thomas; Hantusch, Brigitte; Hoffmann, Thomas Sören; Kenner, Lukas

    2008-01-01

    Stem cells with certain characteristics have become promising tools for molecular medicine. They have the potential to self-regenerate and to differentiate into specific tissues. Besides their great potential, embryonic stem cells (ESC) run the risk of enhanced tumorigenesis. The use of human embryonic stem cells (hESC) is ethically problematic because their isolation involves the destruction of human embryos. Recently developed methods generate are able to pluripotent stem cells from fibroblasts. Alternatives for ESC are adult stem cells (ASC) derived from bone marrow, cord blood, amniotic fluid and other tissues. The following article is on the basis of testimony of Lukas Kenner for the German Bundestag about the use of ESC for research, therapy and drug development. Ethical aspects are taken into consideration.

  6. Stem cell plasticity in development and cancer: epigenetic origin of cancer stem cells.

    PubMed

    Shah, Mansi; Allegrucci, Cinzia

    2013-01-01

    Stem cells are unique cells that can self-renew and differentiate into many cell types. Plasticity is a fundamental characteristic of stem cells and it is regulated by reversible epigenetic modifications. Although gene-restriction programs are established during embryonic development when cell lineages are formed, stem cells retain a degree of flexibility that is essential for tissue regeneration. For instance, quiescent adult stem cells can be induced to proliferate and trans-differentiate in response to injury. The same degree of plasticity is observed in cancer, where cancer cells with stem cell characteristics (or cancer stem cells) are formed by transformation of normal stem cells or de-differentiation of somatic cells. Reprogramming experiments with normal somatic cells and cancer cells show that epigenetic landscapes are more plastic than originally thought and that their manipulation can induce changes in cell fate. Our knowledge of stem cell function is still limited and only by understanding the mechanisms regulating developmental potential together with the definition of epigenetic maps of normal and diseased tissues we can reveal the true extent of their plasticity. In return, the control of plastic epigenetic programs in stem cells will allow us to develop effective treatments for degenerative diseases and cancer. PMID:23150267

  7. The biology of cancer stem cells.

    PubMed

    Lobo, Neethan A; Shimono, Yohei; Qian, Dalong; Clarke, Michael F

    2007-01-01

    Cancers originally develop from normal cells that gain the ability to proliferate aberrantly and eventually turn malignant. These cancerous cells then grow clonally into tumors and eventually have the potential to metastasize. A central question in cancer biology is, which cells can be transformed to form tumors? Recent studies elucidated the presence of cancer stem cells that have the exclusive ability to regenerate tumors. These cancer stem cells share many characteristics with normal stem cells, including self-renewal and differentiation. With the growing evidence that cancer stem cells exist in a wide array of tumors, it is becoming increasingly important to understand the molecular mechanisms that regulate self-renewal and differentiation because corruption of genes involved in these pathways likely participates in tumor growth. This new paradigm of oncogenesis has been validated in a growing list of tumors. Studies of normal and cancer stem cells from the same tissue have shed light on the ontogeny of tumors. That signaling pathways such as Bmi1 and Wnt have similar effects in normal and cancer stem cell self-renewal suggests that common molecular pathways regulate both populations. Understanding the biology of cancer stem cells will contribute to the identification of molecular targets important for future therapies.

  8. Are stem cells a cure for diabetes?

    PubMed

    McCall, Michael D; Toso, Christian; Baetge, Emmanuel E; Shapiro, A M James

    2010-01-01

    With the already heightened demand placed on organ donation, stem cell therapy has become a tantalizing idea to provide glucose-responsive insulin-producing cells to Type 1 diabetic patients as an alternative to islet transplantation. Multiple groups have developed varied approaches to create a population of cells with the appropriate characteristics. Both adult and embryonic stem cells have received an enormous amount of attention as possible sources of insulin-producing cells. Although adult stem cells lack the pluripotent nature of their embryonic counterparts, they appear to avoid the ethical debate that has centred around the latter. This may limit the eventual application of embryonic stem cells, which have already shown promise in early mouse models. One must also consider the potential of stem cells to form teratomas, a complication which would prove devastating in an immunologically compromised transplant recipient. The present review looks at the progress to date in both the adult and embryonic stem cells fields as potential treatments for diabetes. We also consider some of the limitations of stem cell therapy and the potential complications that may develop with their use. PMID:19807695

  9. Translational research of adult stem cell therapy.

    PubMed

    Suzuki, Gen

    2015-11-26

    Congestive heart failure (CHF) secondary to chronic coronary artery disease is a major cause of morbidity and mortality world-wide. Its prevalence is increasing despite advances in medical and device therapies. Cell based therapies generating new cardiomyocytes and vessels have emerged as a promising treatment to reverse functional deterioration and prevent the progression to CHF. Functional efficacy of progenitor cells isolated from the bone marrow and the heart have been evaluated in preclinical large animal models. Furthermore, several clinical trials using autologous and allogeneic stem cells and progenitor cells have demonstrated their safety in humans yet their clinical relevance is inconclusive. This review will discuss the clinical therapeutic applications of three specific adult stem cells that have shown particularly promising regenerative effects in preclinical studies, bone marrow derived mesenchymal stem cell, heart derived cardiosphere-derived cell and cardiac stem cell. We will also discuss future therapeutic approaches.

  10. Practical Integration-Free Episomal Methods for Generating Human Induced Pluripotent Stem Cells.

    PubMed

    Kime, Cody; Rand, Tim A; Ivey, Kathryn N; Srivastava, Deepak; Yamanaka, Shinya; Tomoda, Kiichiro

    2015-01-01

    The advent of induced pluripotent stem (iPS) cell technology has revolutionized biomedicine and basic research by yielding cells with embryonic stem (ES) cell-like properties. The use of iPS-derived cells for cell-based therapies and modeling of human disease holds great potential. While the initial description of iPS cells involved overexpression of four transcription factors via viral vectors that integrated within genomic DNA, advances in recent years by our group and others have led to safer and higher quality iPS cells with greater efficiency. Here, we describe commonly practiced methods for non-integrating induced pluripotent stem cell generation using nucleofection of episomal reprogramming plasmids. These methods are adapted from recent studies that demonstrate increased hiPS cell reprogramming efficacy with the application of three powerful episomal hiPS cell reprogramming factor vectors and the inclusion of an accessory vector expressing EBNA1.

  11. An Aminopeptidase in the Drosophila Testicular Niche Acts in Germline Stem Cell Maintenance and Spermatogonial Dedifferentiation.

    PubMed

    Lim, Cindy; Gandhi, Shiv; Biniossek, Martin L; Feng, Lijuan; Schilling, Oliver; Urban, Siniša; Chen, Xin

    2015-10-13

    Extrinsic cues from the niche are known to regulate adult stem cell self-renewal versus differentiation. Here, we report that an aminopeptidase Slamdance (Sda) acts in the Drosophila testicular niche to maintain germline stem cells (GSCs) and regulate progenitor germ cell dedifferentiation. Mutations in sda lead to dramatic testicular niche deterioration and stem cell loss. Recombinant Sda has specific aminopeptidase activity in vitro, and the in vivo function of Sda requires an intact aminopeptidase domain. Sda is required for accumulation of mature DE-cadherin, and overexpression of DE-cadherin rescues most sda mutant phenotypes, suggesting that DE-cadherin is an important target of Sda. Finally, Sda is both necessary and sufficient to promote dedifferentiation during aging and recovery from genetically manipulated depletion of GSCs. Together, our results suggest that a niche factor promotes both stem cell maintenance and progenitor cell dedifferentiation.

  12. An Aminopeptidase in the Drosophila Testicular Niche Acts in Germline Stem Cell Maintenance and Spermatogonial Dedifferentiation.

    PubMed

    Lim, Cindy; Gandhi, Shiv; Biniossek, Martin L; Feng, Lijuan; Schilling, Oliver; Urban, Siniša; Chen, Xin

    2015-10-13

    Extrinsic cues from the niche are known to regulate adult stem cell self-renewal versus differentiation. Here, we report that an aminopeptidase Slamdance (Sda) acts in the Drosophila testicular niche to maintain germline stem cells (GSCs) and regulate progenitor germ cell dedifferentiation. Mutations in sda lead to dramatic testicular niche deterioration and stem cell loss. Recombinant Sda has specific aminopeptidase activity in vitro, and the in vivo function of Sda requires an intact aminopeptidase domain. Sda is required for accumulation of mature DE-cadherin, and overexpression of DE-cadherin rescues most sda mutant phenotypes, suggesting that DE-cadherin is an important target of Sda. Finally, Sda is both necessary and sufficient to promote dedifferentiation during aging and recovery from genetically manipulated depletion of GSCs. Together, our results suggest that a niche factor promotes both stem cell maintenance and progenitor cell dedifferentiation. PMID:26440886

  13. Human adipose stem cells: current clinical applications.

    PubMed

    Gir, Phanette; Oni, Georgette; Brown, Spencer A; Mojallal, Ali; Rohrich, Rod J

    2012-06-01

    Adipose-derived stem cells are multipotent cells that can easily be extracted from adipose tissue, are capable of expansion in vitro, and have the capacity to differentiate into multiple cell lineages, which have the potential for use in regenerative medicine. However, several issues need to be studied to determine safe human use. For example, there are questions related to isolation and purification of adipose-derived stem cells, their effect on tumor growth, and the enforcement of U.S. Food and Drug Administration regulations. Numerous studies have been published, with the interest in the potential for regenerative medicine continually growing. Several clinical trials using human adipose stem cell therapy are currently being performed around the world, and there has been a rapid evolution and expansion of their number. The purpose of this article was to review the current published basic science evidence and ongoing clinical trials involving the use of adipose-derived stem cells in plastic surgery and in regenerative medicine in general. The results of the studies and clinical trials using adipose-derived stem cells reported in this review seem to be promising not only in plastic surgery but also in a wide variety of other specialties. Nevertheless, those reported showed disparity in the way adipose-derived stem cells were used. Further basic science experimental studies with standardized protocols and larger randomized trials need to be performed to ensure safety and efficacy of adipose-derived stem cells use in accordance with U.S. Food and Drug Administration guidelines.

  14. [Stem cells: limitations and opportunities in Peru].

    PubMed

    Amiel-Pérez, José; Casado, Fanny

    2015-10-01

    Stem cells are defined as rare cells that are characterized by asymmetric division, a process known as self-renewal, and the potential to differentiate into more than one type of terminally differentiated cell. There is a diversity of stem cells including embryonic stem cells, which exist only during the first stages of human development, and many adult stem cells depending on the specific tissues from where they derive or the ones derived from mesenchymal or stromal tissues. On the other hand, there are induced pluripotent stem cells generated by genetic engineering with similar properties to embryonic stem cells that are derived from adult tissues without the ethical and legal limitations. In all cases, there are many questions that are being addressed by research in basic sciences to better inform clinical practice. In Peru, there is much to do refining techniques and improving methodologies, which requires experience, proper facilities and highly specialized human resources. However, there are interesting efforts to place Peruvian stem cell research in the international scientific arena.

  15. High Throughput Optimization of Stem Cell Microenvironments

    PubMed Central

    Yang, Fan; Mei, Ying; Langer, Robert; Anderson, Daniel G.

    2009-01-01

    Stem cells have great potential as cell sources for regenerative medicine due to both their self-renewal and multi-lineage differentiation capacity. Despite advances in the field of stem cell biology, major challenges remain before stem cells can be widely used for therapeutic purposes. One challenge is to develop reproducible methods to control stem cell growth and differentiation. The niche in which stem cells reside is a complex, multi-factorial environment. In contrast to using cells alone, biomaterials can provide initial structural support, and allow cells to adhere, proliferate and differentiate in a three-dimensional environment. Researchers have incorporated signals into the biomaterials that can promote desired cell functions in a spatially and temporally controlled manner. Despite progress in biomaterial design and methods to modulate cellular behavior, many of the complex signal networks that regulate cell-material interactions remain unclear. Due to the vast numbers of material properties to be explored and the complexity of cell-surface interactions, it is often difficult to optimize stem cell microenvironments using conventional, iterative approaches. To address these challenges, high throughput screening of combinatorial libraries has emerged as a novel approach to achieve rapid screening with reduced materials and costs. In this review, we discuss recent research in the area of high throughput approaches for characterization and optimization of cellular interactions with their microenvironments. In contrast to conventional approaches, screening combinatorial libraries can result in the discovery of unexpected material solutions to these complex problems. PMID:19601753

  16. Connecting Mitochondria, Metabolism, and Stem Cell Fate

    PubMed Central

    Wanet, Anaïs; Arnould, Thierry; Najimi, Mustapha

    2015-01-01

    As sites of cellular respiration and energy production, mitochondria play a central role in cell metabolism. Cell differentiation is associated with an increase in mitochondrial content and activity and with a metabolic shift toward increased oxidative phosphorylation activity. The opposite occurs during reprogramming of somatic cells into induced pluripotent stem cells. Studies have provided evidence of mitochondrial and metabolic changes during the differentiation of both embryonic and somatic (or adult) stem cells (SSCs), such as hematopoietic stem cells, mesenchymal stem cells, and tissue-specific progenitor cells. We thus propose to consider those mitochondrial and metabolic changes as hallmarks of differentiation processes. We review how mitochondrial biogenesis, dynamics, and function are directly involved in embryonic and SSC differentiation and how metabolic and sensing pathways connect mitochondria and metabolism with cell fate and pluripotency. Understanding the basis of the crosstalk between mitochondria and cell fate is of critical importance, given the promising application of stem cells in regenerative medicine. In addition to the development of novel strategies to improve the in vitro lineage-directed differentiation of stem cells, understanding the molecular basis of this interplay could lead to the identification of novel targets to improve the treatment of degenerative diseases. PMID:26134242

  17. Connecting Mitochondria, Metabolism, and Stem Cell Fate.

    PubMed

    Wanet, Anaïs; Arnould, Thierry; Najimi, Mustapha; Renard, Patricia

    2015-09-01

    As sites of cellular respiration and energy production, mitochondria play a central role in cell metabolism. Cell differentiation is associated with an increase in mitochondrial content and activity and with a metabolic shift toward increased oxidative phosphorylation activity. The opposite occurs during reprogramming of somatic cells into induced pluripotent stem cells. Studies have provided evidence of mitochondrial and metabolic changes during the differentiation of both embryonic and somatic (or adult) stem cells (SSCs), such as hematopoietic stem cells, mesenchymal stem cells, and tissue-specific progenitor cells. We thus propose to consider those mitochondrial and metabolic changes as hallmarks of differentiation processes. We review how mitochondrial biogenesis, dynamics, and function are directly involved in embryonic and SSC differentiation and how metabolic and sensing pathways connect mitochondria and metabolism with cell fate and pluripotency. Understanding the basis of the crosstalk between mitochondria and cell fate is of critical importance, given the promising application of stem cells in regenerative medicine. In addition to the development of novel strategies to improve the in vitro lineage-directed differentiation of stem cells, understanding the molecular basis of this interplay could lead to the identification of novel targets to improve the treatment of degenerative diseases.

  18. Induced pluripotent stem cell technology in regenerative medicine and biology.

    PubMed

    Pei, Duanqing; Xu, Jianyong; Zhuang, Qiang; Tse, Hung-Fat; Esteban, Miguel A

    2010-01-01

    The potential of human embryonic stem cells (ESCs) for regenerative medicine is unquestionable, but practical and ethical considerations have hampered clinical application and research. In an attempt to overcome these issues, the conversion of somatic cells into pluripotent stem cells similar to ESCs, commonly termed nuclear reprogramming, has been a top objective of contemporary biology. More than 40 years ago, King, Briggs, and Gurdon pioneered somatic cell nuclear reprogramming in frogs, and in 1981 Evans successfully isolated mouse ESCs. In 1997 Wilmut and collaborators produced the first cloned mammal using nuclear transfer, and then Thomson obtained human ESCs from in vitro fertilized blastocysts in 1998. Over the last 2 decades we have also seen remarkable findings regarding how ESC behavior is controlled, the importance of which should not be underestimated. This knowledge allowed the laboratory of Shinya Yamanaka to overcome brilliantly conceptual and technical barriers in 2006 and generate induced pluripotent stem cells (iPSCs) from mouse fibroblasts by overexpressing defined combinations of ESC-enriched transcription factors. Here, we discuss some important implications of human iPSCs for biology and medicine and also point to possible future directions.

  19. Induced Pluripotent Stem Cell Technology in Regenerative Medicine and Biology

    NASA Astrophysics Data System (ADS)

    Pei, Duanqing; Xu, Jianyong; Zhuang, Qiang; Tse, Hung-Fat; Esteban, Miguel A.

    The potential of human embryonic stem cells (ESCs) for regenerative medicine is unquestionable, but practical and ethical considerations have hampered clinical application and research. In an attempt to overcome these issues, the conversion of somatic cells into pluripotent stem cells similar to ESCs, commonly termed nuclear reprogramming, has been a top objective of contemporary biology. More than 40 years ago, King, Briggs, and Gurdon pioneered somatic cell nuclear reprogramming in frogs, and in 1981 Evans successfully isolated mouse ESCs. In 1997 Wilmut and collaborators produced the first cloned mammal using nuclear transfer, and then Thomson obtained human ESCs from in vitro fertilized blastocysts in 1998. Over the last 2 decades we have also seen remarkable findings regarding how ESC behavior is controlled, the importance of which should not be underestimated. This knowledge allowed the laboratory of Shinya Yamanaka to overcome brilliantly conceptual and technical barriers in 2006 and generate induced pluripotent stem cells (iPSCs) from mouse fibroblasts by overexpressing defined combinations of ESC-enriched transcription factors. Here, we discuss some important implications of human iPSCs for biology and medicine and also point to possible future directions.

  20. Calcium signaling in pluripotent stem cells.

    PubMed

    Apáti, Ágota; Pászty, Katalin; Erdei, Zsuzsa; Szebényi, Kornélia; Homolya, László; Sarkadi, Balázs

    2012-04-28

    Pluripotent stem cells represent a new source of biological material allowing the exploration of signaling phenomena during normal cell development and differentiation. Still, the calcium signaling pathways and intracellular calcium responses to various ligands or stress conditions have not been sufficiently explored as yet in embryonic or induced pluripotent stem cells and in their differentiated offspring. This is partly due to the special culturing conditions of these cell types, the rapid morphological and functional changes in heterogeneous cell populations during early differentiation, and methodological problems in cellular calcium measurements. In this paper, we review the currently available data in the literature on calcium signaling in pluripotent stem cells and discuss the potential shortcomings of these studies. Various assay methods are surveyed for obtaining reliable data both in undifferentiated embryonic stem cells and in specific, stem cell-derived human tissues. In this paper, we present the modulation of calcium signaling in human embryonic stem cells (hESC) and in their derivates; mesenchymal stem cell like (MSCl) cells and cardiac tissues using the fluorescent calcium indicator Fluo-4 and confocal microscopy. LPA, trypsin and angiotensin II were effective in inducing calcium signals both in HUES9 and MSCl cells. Histamine and thrombin induced calcium signal exclusively in the MSCl cells, while ATP was effective only in HUES9 cells. There was no calcium signal evoked by GABA, even at relatively high concentrations. In stem cell-derived cardiomyocytes a rapid increase in the beating rate and an increase of the calcium signal peaks could be observed after the addition of adrenaline, while verapamil led to a strong decrease in cellular calcium and stopped spontaneous contractions in a relaxed state.

  1. Stem cells and small molecule screening: haploid embryonic stem cells as a new tool.

    PubMed

    Wu, Bi; Li, Wei; Wang, Liu; Liu, Zhong-hua; Zhao, Xiao-yang

    2013-06-01

    Stem cells can both self-renew and differentiate into various cell types under certain conditions, which makes them a good model for development and disease studies. Recently, chemical approaches have been widely applied in stem cell biology by promoting stem cell self-renewal, proliferation, differentiation and somatic cell reprogramming using specific small molecules. Conversely, stem cells and their derivatives also provide an efficient and robust platform for small molecule and drug screening. Here, we review the current research and applications of small molecules that modulate stem cell self-renewal and differentiation and improve reprogramming, as well as the applications that use stem cells as a tool for small molecule screening. Moreover, we introduce the recent advance in haploid embryonic stem cells research. Haploid embryonic stem cells maintain haploidy and stable growth over extensive passages, possess the ability to differentiate into all three germ layers in vitro and in vivo, and contribute to the germlines of chimeras when injected into blastocysts. Androgenetic haploid stem cells can also be used in place of sperm to produce fertile progeny after intracytoplasmic injection into mature oocytes. Such characteristics demonstrate that haploid stem cells are a new approach for genetic studies at both the cellular and animal levels and that they are a valuable platform for future small molecule screening.

  2. Ameliorating replicative senescence of human bone marrow stromal cells by PSMB5 overexpression

    SciTech Connect

    Lu, Li; Song, Hui-Fang; Wei, Jiao-Long; Liu, Xue-Qin; Song, Wen-Hui; Yan, Ba-Yi; Yang, Gui-Jiao; Li, Ang; Yang, Wu-Lin

    2014-01-24

    Highlights: • PSMB5 overexpression restores the differentiation potential of aged hBMSCs. • PSMB5 overexpression enhances the proteasomal activity of late-stage hBMSCs. • PSMB5 overexpression inhibits replicative senescence and improved cell viability. • PSMB5 overexpression promotes cell growth by upregulating the Cyclin D1/CDK4 complex. - Abstract: Multipotent human bone marrow stromal cells (hBMSCs) potentially serve as a source for cell-based therapy in regenerative medicine. However, in vitro expansion was inescapably accompanied with cell senescence, characterized by inhibited proliferation and compromised pluripotency. We have previously demonstrated that this aging process is closely associated with reduced 20S proteasomal activity, with down-regulation of rate-limiting catalytic β-subunits particularly evident. In the present study, we confirmed that proteasomal activity directly contributes to senescence of hBMSCs, which could be reversed by overexpression of the β5-subunit (PSMB5). Knocking down PSMB5 led to decreased proteasomal activity concurrent with reduced cell proliferation in early-stage hBMSCs, which is similar to the senescent phenotype observed in late-stage cells. In contrast, overexpressing PSMB5 in late-stage cells efficiently restored the normal activity of 20S proteasomes and promoted cell growth, possibly via upregulating the Cyclin D1/CDK4 complex. Additionally, PSMB5 could enhance cell resistance to oxidative stress, as evidenced by the increased cell survival upon exposing senescent hBMSCs to hydrogen peroxide. Furthermore, PSMB5 overexpression retained the pluripotency of late-stage hBMSCs by facilitating their neural differentiation both in vitro and in vivo. Collectively, our work reveals a critical role of PSMB5 in 20S proteasome-mediated protection against replicative senescence, pointing to a possible strategy for maintaining the integrity of culture-expanded hBMSCs by manipulating the expression of PSMB5.

  3. Bioreactor Engineering of Stem Cell Environments

    PubMed Central

    Tandon, Nina; Marolt, Darja; Cimetta, Elisa; Vunjak-Novakovic, Gordana

    2013-01-01

    Stem cells hold promise to revolutionize modern medicine by development of new therapies, disease models and drug screening systems. Standard cell culture systems have limited biological relevance because they do not recapitulate the complex 3-dimensional interactions and biophysical cues that characterize the in vivo environment. In this review, we discuss the current advances in engineering stem cell environments using novel biomaterials and bioreactor technologies. We also reflect on the challenges the field is currently facing with regard to translation of stem cell based therapies into the clinic. PMID:23531529

  4. Update on small intestinal stem cells

    PubMed Central

    Tesori, Valentina; Puglisi, Maria Ausiliatrice; Lattanzi, Wanda; Gasbarrini, Giovanni Battista; Gasbarrini, Antonio

    2013-01-01

    Among somatic stem cells, those residing in the intestine represent a fascinating and poorly explored research field. Particularly, somatic stem cells reside in the small intestine at the level of the crypt base, in a constant balance between self-renewal and differentiation. Aim of the present review is to delve into the mechanisms that regulate the delicate equilibrium through which intestinal stem cells orchestrate intestinal architecture. To this aim, special focus will be addressed to identify the integrating signals from the surrounding niche, supporting a model whereby distinct cell populations facilitate homeostatic vs injury-induced regeneration. PMID:23922464

  5. Stem cell applications in military medicine.

    PubMed

    Christopherson, Gregory T; Nesti, Leon J

    2011-10-19

    There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers--and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research.

  6. Current understanding concerning intestinal stem cells

    PubMed Central

    Cui, Shuang; Chang, Peng-Yu

    2016-01-01

    In mammals, the intestinal epithelium is a tissue that contains two distinct pools of stem cells: active intestinal stem cells and reserve intestinal stem cells. The former are located in the crypt basement membrane and are responsible for maintaining epithelial homeostasis under intact conditions, whereas the latter exhibit the capacity to facilitate epithelial regeneration after injury. These two pools of cells can convert into each other, maintaining their quantitative balance. In terms of the active intestinal stem cells, their development into functional epithelium is precisely controlled by the following signaling pathways: Wnt/β-catenin, Ras/Raf/Mek/Erk/MAPK, Notch and BMP/Smad. However, mutations in some of the key regulator genes associated with these signaling pathways, such as APC, Kras and Smad4, are also highly associated with gut malformations. At this point, clarifying the biological characteristics of intestinal stem cells will increase the feasibility of preventing or treating some intestinal diseases, such as colorectal cancer. Moreover, as preclinical data demonstrate the therapeutic effects of colon stem cells on murine models of experimental colitis, the prospects of stem cell-based regenerative treatments for ulcerous lesions in the gastrointestinal tract will be improved all the same.

  7. Current understanding concerning intestinal stem cells

    PubMed Central

    Cui, Shuang; Chang, Peng-Yu

    2016-01-01

    In mammals, the intestinal epithelium is a tissue that contains two distinct pools of stem cells: active intestinal stem cells and reserve intestinal stem cells. The former are located in the crypt basement membrane and are responsible for maintaining epithelial homeostasis under intact conditions, whereas the latter exhibit the capacity to facilitate epithelial regeneration after injury. These two pools of cells can convert into each other, maintaining their quantitative balance. In terms of the active intestinal stem cells, their development into functional epithelium is precisely controlled by the following signaling pathways: Wnt/β-catenin, Ras/Raf/Mek/Erk/MAPK, Notch and BMP/Smad. However, mutations in some of the key regulator genes associated with these signaling pathways, such as APC, Kras and Smad4, are also highly associated with gut malformations. At this point, clarifying the biological characteristics of intestinal stem cells will increase the feasibility of preventing or treating some intestinal diseases, such as colorectal cancer. Moreover, as preclinical data demonstrate the therapeutic effects of colon stem cells on murine models of experimental colitis, the prospects of stem cell-based regenerative treatments for ulcerous lesions in the gastrointestinal tract will be improved all the same. PMID:27610020

  8. Stem cell applications in military medicine.

    PubMed

    Christopherson, Gregory T; Nesti, Leon J

    2011-01-01

    There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers--and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research. PMID:22011454

  9. Current understanding concerning intestinal stem cells.

    PubMed

    Cui, Shuang; Chang, Peng-Yu

    2016-08-21

    In mammals, the intestinal epithelium is a tissue that contains two distinct pools of stem cells: active intestinal stem cells and reserve intestinal stem cells. The former are located in the crypt basement membrane and are responsible for maintaining epithelial homeostasis under intact conditions, whereas the latter exhibit the capacity to facilitate epithelial regeneration after injury. These two pools of cells can convert into each other, maintaining their quantitative balance. In terms of the active intestinal stem cells, their development into functional epithelium is precisely controlled by the following signaling pathways: Wnt/β-catenin, Ras/Raf/Mek/Erk/MAPK, Notch and BMP/Smad. However, mutations in some of the key regulator genes associated with these signaling pathways, such as APC, Kras and Smad4, are also highly associated with gut malformations. At this point, clarifying the biological characteristics of intestinal stem cells will increase the feasibility of preventing or treating some intestinal diseases, such as colorectal cancer. Moreover, as preclinical data demonstrate the therapeutic effects of colon stem cells on murine models of experimental colitis, the prospects of stem cell-based regenerative treatments for ulcerous lesions in the gastrointestinal tract will be improved all the same. PMID:27610020

  10. Stem cell tracking using iron oxide nanoparticles.

    PubMed

    Bull, Elizabeth; Madani, Seyed Yazdan; Sheth, Roosey; Seifalian, Amelia; Green, Mark; Seifalian, Alexander M

    2014-01-01

    Superparamagnetic iron oxide nanoparticles (SPIONs) are an exciting advancement in the field of nanotechnology. They expand the possibilities of noninvasive analysis and have many useful properties, making them potential candidates for numerous novel applications. Notably, they have been shown that they can be tracked by magnetic resonance imaging (MRI) and are capable of conjugation with various cell types, including stem cells. In-depth research has been undertaken to establish these benefits, so that a deeper level of understanding of stem cell migratory pathways and differentiation, tumor migration, and improved drug delivery can be achieved. Stem cells have the ability to treat and cure many debilitating diseases with limited side effects, but a main problem that arises is in the noninvasive tracking and analysis of these stem cells. Recently, researchers have acknowledged the use of SPIONs for this purpose and have set out to establish suitable protocols for coating and attachment, so as to bring MRI tracking of SPION-labeled stem cells into common practice. This review paper explains the manner in which SPIONs are produced, conjugated, and tracked using MRI, as well as a discussion on their limitations. A concise summary of recently researched magnetic particle coatings is provided, and the effects of SPIONs on stem cells are evaluated, while animal and human studies investigating the role of SPIONs in stem cell tracking will be explored.

  11. Stem cells: public policy and ethics.

    PubMed

    Towns, Cindy R; Jones, D Gareth

    2004-02-01

    Debate on the regulation of human stem cells needs to bring together scientific, ethical and policy considerations if it is to be adequately informed. Scientific issues of importance include the relevance of the environment in appreciating the extent of stem cell plasticity, and the relative potential of embryonic and adult stem cells to produce other cell types. An awareness that blastocysts (early embryos) and stem cells in the laboratory are pluripotential and not totipotential has implications for ethical and policy debate. The regulations on stem cell research are reviewed, showing that four positions have emerged. Position A corresponds to the prohibition of all embryo research, position B confines the use of embryonic stem cells to those currently in existence and therefore extracted prior to some specified date, position C allows for the use and ongoing isolation of embryonic stem cells from surplus in vitro fertilization embryos, and position D approves of the creation of human embryos specifically for research. Position B which has been adopted by the United States, Germany, and Australia (with subtle differences between them) and which is regarded as a compromise position, is critiqued. This is principally on the basis that, in spite of claims made about it, the ongoing destruction of human embryos will continue. This is because these countries allow in vitro fertilization programs, inherent within which is embryo destruction. It is argued that position C would be a more consistent ethical position for these countries. The possibility of moving to position D is also raised.

  12. Stem cell applications in military medicine

    PubMed Central

    2011-01-01

    There are many similarities between health issues affecting military and civilian patient populations, with the exception of the relatively small but vital segment of active soldiers who experience high-energy blast injuries during combat. A rising incidence of major injuries from explosive devices in recent campaigns has further complicated treatment and recovery, highlighting the need for tissue regenerative options and intensifying interest in the possible role of stem cells for military medicine. In this review we outline the array of tissue-specific injuries typically seen in modern combat - as well as address a few complications unique to soldiers - and discuss the state of current stem cell research in addressing each area. Embryonic, induced-pluripotent and adult stem cell sources are defined, along with advantages and disadvantages unique to each cell type. More detailed stem cell sources are described in the context of each tissue of interest, including neural, cardiopulmonary, musculoskeletal and sensory tissues, with brief discussion of their potential role in regenerative medicine moving forward. Additional commentary is given to military stem cell applications aside from regenerative medicine, such as blood pharming, immunomodulation and drug screening, with an overview of stem cell banking and the unique opportunity provided by the military and civilian overlap of stem cell research. PMID:22011454

  13. β-Cell-Specific Mafk Overexpression Impairs Pancreatic Endocrine Cell Development.

    PubMed

    Abdellatif, Ahmed M; Oishi, Hisashi; Itagaki, Takahiro; Jung, Yunshin; Shawki, Hossam H; Okita, Yukari; Hasegawa, Yoshikazu; Suzuki, Hiroyuki; El-Morsy, Salah E; El-Sayed, Mesbah A; Shoaib, Mahmoud B; Sugiyama, Fumihiro; Takahashi, Satoru

    2016-01-01

    The MAF family transcription factors are homologs of v-Maf, the oncogenic component of the avian retrovirus AS42. They are subdivided into 2 groups, small and large MAF proteins, according to their structure, function, and molecular size. MAFK is a member of the small MAF family and acts as a dominant negative form of large MAFs. In previous research we generated transgenic mice that overexpress MAFK in order to suppress the function of large MAF proteins in pancreatic β-cells. These mice developed hyperglycemia in adulthood due to impairment of glucose-stimulated insulin secretion. The aim of the current study is to examine the effects of β-cell-specific Mafk overexpression in endocrine cell development. The developing islets of Mafk-transgenic embryos appeared to be disorganized with an inversion of total numbers of insulin+ and glucagon+ cells due to reduced β-cell proliferation. Gene expression analysis by quantitative RT-PCR revealed decreased levels of β-cell-related genes whose expressions are known to be controlled by large MAF proteins. Additionally, these changes were accompanied with a significant increase in key β-cell transcription factors likely due to compensatory mechanisms that might have been activated in response to the β-cell loss. Finally, microarray comparison of gene expression profiles between wild-type and transgenic pancreata revealed alteration of some uncharacterized genes including Pcbd1, Fam132a, Cryba2, and Npy, which might play important roles during pancreatic endocrine development. Taken together, these results suggest that Mafk overexpression impairs endocrine development through a regulation of numerous β-cell-related genes. The microarray analysis provided a unique data set of differentially expressed genes that might contribute to a better understanding of the molecular basis that governs the development and function of endocrine pancreas. PMID:26901059

  14. β-Cell-Specific Mafk Overexpression Impairs Pancreatic Endocrine Cell Development

    PubMed Central

    Abdellatif, Ahmed M.; Oishi, Hisashi; Itagaki, Takahiro; Jung, Yunshin; Shawki, Hossam H.; Okita, Yukari; Hasegawa, Yoshikazu; Suzuki, Hiroyuki; El-Morsy, Salah E.; El-Sayed, Mesbah A.; Shoaib, Mahmoud B.; Sugiyama, Fumihiro; Takahashi, Satoru

    2016-01-01

    The MAF family transcription factors are homologs of v-Maf, the oncogenic component of the avian retrovirus AS42. They are subdivided into 2 groups, small and large MAF proteins, according to their structure, function, and molecular size. MAFK is a member of the small MAF family and acts as a dominant negative form of large MAFs. In previous research we generated transgenic mice that overexpress MAFK in order to suppress the function of large MAF proteins in pancreatic β-cells. These mice developed hyperglycemia in adulthood due to impairment of glucose-stimulated insulin secretion. The aim of the current study is to examine the effects of β-cell-specific Mafk overexpression in endocrine cell development. The developing islets of Mafk-transgenic embryos appeared to be disorganized with an inversion of total numbers of insulin+ and glucagon+ cells due to reduced β-cell proliferation. Gene expression analysis by quantitative RT-PCR revealed decreased levels of β-cell-related genes whose expressions are known to be controlled by large MAF proteins. Additionally, these changes were accompanied with a significant increase in key β-cell transcription factors likely due to compensatory mechanisms that might have been activated in response to the β-cell loss. Finally, microarray comparison of gene expression profiles between wild-type and transgenic pancreata revealed alteration of some uncharacterized genes including Pcbd1, Fam132a, Cryba2, and Npy, which might play important roles during pancreatic endocrine development. Taken together, these results suggest that Mafk overexpression impairs endocrine development through a regulation of numerous β-cell-related genes. The microarray analysis provided a unique data set of differentially expressed genes that might contribute to a better understanding of the molecular basis that governs the development and function of endocrine pancreas. PMID:26901059

  15. Immunohistochemical study of hair follicle stem cells in regenerated hair follicles induced by Wnt10b

    PubMed Central

    Zhang, Yiming; Xing, Yizhan; Guo, Haiying; Ma, Xiaogen; Li, Yuhong

    2016-01-01

    The regulation of the periodic regeneration of hair follicles is complicated. Although Wnt10b has been reported to induce hair follicle regeneration, the characteristics of induced hair follicles, especially the target cells of Wnt10b, have not yet been clearly elucidated. Thus, we systematically evaluated the expression and proliferation patterns of Wnt10b-induced hair follicles. We found that Wnt10b promoted the proliferation of hair follicle stem cells from 24 hours after AdWnt10b injection. Seventy-two hours after AdWnt10b injection, cells outside of bulge area began to proliferate. When the induced hair follicle entered full anagen, although the hair follicle stem cells were normal, canonical Wnt signaling was maintained in the hair precortex cells. Our results reveal that the target cells that overexpressed Wnt10b included hair follicle stem cells, hair precortex cells, and matrix cells. PMID:27766026

  16. Stem cells as promising therapeutic options for neurological disorders.

    PubMed

    Yoo, Jongman; Kim, Han-Soo; Hwang, Dong-Youn

    2013-04-01

    Due to the limitations of pharmacological and other current therapeutic strategies, stem cell therapies have emerged as promising options for treating many incurable neurologic diseases. A variety of stem cells including pluripotent stem cells (i.e., embryonic stem cells and induced pluripotent stem cells) and multipotent adult stem cells (i.e., fetal brain tissue, neural stem cells, and mesenchymal stem cells from various sources) have been explored as therapeutic options for treating many neurologic diseases, and it is becoming obvious that each type of stem cell has pros and cons as a source for cell therapy. Wise selection of stem cells with regard to the nature and status of neurologic dysfunctions is required to achieve optimal therapeutic efficacy. To this aim, the stem cell-mediated therapeutic efforts on four major neurological diseases, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and stroke, will be introduced, and current problems and future directions will be discussed.

  17. Stem Cells Antigen-1 Enriches for a Cancer Stem Cell-Like Subpopulation in Mouse Gastric Cancer.

    PubMed

    Park, Jun Won; Park, Jung Min; Park, Dong Min; Kim, Dae-Yong; Kim, Hark Kyun

    2016-05-01

    There is a strong need to identify markers to enrich gastric cancer stem cells (CSCs). However, CSC enrichment markers for mouse gastric cancers have not yet been determined. In our previous study, we generated primary mouse gastric cancer cell line NCC-S1 (S1) established from a Villin-cre;Smad4(F/F) ;Trp53(F/F) ;Cdh1(F/wt) mouse and its metastatic variant cell line NCC-S1M (S1M). Interestingly, S1M cells exhibited CSC-like features, such as increased tumorigenic potential and chemoresistance. By comparing gene expression profiles between S1 and S1M cells, we identified Stem Cells Antigen-1 (Sca-1) as a cell surface marker, which was mostly upregulated in S1M. Sca-1 was upregulated in tumorspheres from S1 cells or after cisplatin treatment in S1 cells. Immunofluorescence (IF) analysis showed that approximately 7% of cancer cells exhibited positivity for Sca-1 in primary mouse gastric cancer tissues. An in vivo-limiting dilution assay showed that Sca-1(high) mouse gastric cancer cells demonstrated increased tumorigenicity compared with Sca-1(negative) cells. The Sca-1 expression was downregulated by TGF-β pathway activation and Wnt pathway inhibition in mouse gastric cancer cells. Sca-1(high) cells showed relatively low TGF-β reporter activity and high TCF/LEF1 reporter activity compared with Sca-1(negative) cells. A chromatin immunoprecipitation analysis demonstrated that Sca-1 was a β-catenin/LEF1 target gene. Sca-1(high) allografts were more resistant to cisplatin/fluorouracil chemotherapy than Sca-1(negative) allografts, and overexpressed Bcl-xL. Eighty-five mouse genes overexpressed in Sca-1(high) S1 cells compared with Sca-1(negative) cells clustered 123 pretreatment gastric cancer patient samples according to survival following chemotherapy. Taken together, Sca-1 is a novel CSC enrichment marker that mediates TGF-β and Wnt/β-catenin signaling in mouse gastric cancer. Stem Cells 2016;34:1177-1187. PMID:26869189

  18. Human germ cell differentiation from fetal- and adult-derived induced pluripotent stem cells

    PubMed Central

    Panula, Sarita; Medrano, Jose V.; Kee, Kehkooi; Bergström, Rosita; Nguyen, Ha Nam; Byers, Blake; Wilson, Kitchener D.; Wu, Joseph C.; Simon, Carlos; Hovatta, Outi; Reijo Pera, Renee A.

    2011-01-01

    Historically, our understanding of molecular genetic aspects of human germ cell development has been limited, at least in part due to inaccessibility of early stages of human development to experimentation. However, the derivation of pluripotent stem cells may provide the necessary human genetic system to study germ cell development. In this study, we compared the potential of human induced pluripotent stem cells (iPSCs), derived from adult and fetal somatic cells to form primordial and meiotic germ cells, relative to human embryonic stem cells. We found that ∼5% of human iPSCs differentiated to primordial germ cells (PGCs) following induction with bone morphogenetic proteins. Furthermore, we observed that PGCs expressed green fluorescent protein from a germ cell-specific reporter and were enriched for the expression of endogenous germ cell-specific proteins and mRNAs. In response to the overexpression of intrinsic regulators, we also observed that iPSCs formed meiotic cells with extensive synaptonemal complexes and post-meiotic haploid cells with a similar pattern of ACROSIN staining as observed in human spermatids. These results indicate that human iPSCs derived from reprogramming of adult somatic cells can form germline cells. This system may provide a useful model for molecular genetic studies of human germline formation and pathology and a novel platform for clinical studies and potential therapeutical applications. PMID:21131292

  19. Immunological characteristics of mesenchymal stem cells

    PubMed Central

    Machado, Cíntia de Vasconcellos; Telles, Paloma Dias da Silva; Nascimento, Ivana Lucia Oliveira

    2013-01-01

    Although bone marrow is the main source, mesenchymal stem cells have already been isolated from various other tissues, such as the liver, pancreas, adipose tissue, peripheral blood and dental pulp. These plastic adherent cells are morphologically similar to fibroblasts and have a high proliferative potential. This special group of cells possesses two essential characteristics: self-renewal and differentiation, with appropriate stimuli, into various cell types. Mesenchymal stem cells are considered immunologically privileged, since they do not express costimulatory molecules, required for complete T cell activation, on their surface. Several studies have shown that these cells exert an immunosuppressive effect on cells from both innate and acquired immunity systems. Mesenchymal stem cells can regulate the immune response in vitro by inhibiting the maturation of dendritic cells, as well as by suppressing the proliferation and function of T and B lymphocytes and natural killer cells. These special properties of mesenchymal stem cells make them a promising strategy in the treatment of immune mediated disorders, such as graft-versus-host disease and autoimmune diseases, as well as in regenerative medicine. The understanding of immune regulation mechanisms of mesenchymal stem cells, and also those involved in the differentiation of these cells in various lineages is primordial for their successful and safe application in different areas of medicine. PMID:23580887

  20. [Stem cells in cardiological clinical trials].

    PubMed

    Przybycień, Krzysztof; Kornacewicz Jach, Zdzisława; Machaliński, Bogusław

    2011-01-01

    Stem cell-based therapy is a novel therapeutic strategy introduced into cardiology, although there are not any established standards within the stem/progenitor cell type employed, their preparation, rout of administration as well as methods controlling the pathophysiological and clinical parameters after the cell application. The aim of the present work was a complex meta-analysis of the clinical trials carried out in this field. Over 1000 patients with myocardial infarction as well as circulatory failure have been treated with stem cell-based therapy so far, but the obtained results are not concordant. Progress within cell biology and biotechnology give hopes for development of more effective therapeutic approaches. Identification and isolation of cardiac- -specific stem/progenitor cells may deliver new perspectives for such therapy in the nearest future.

  1. Seeing Stem Cells at Work In Vivo

    PubMed Central

    Srivastava, Amit K.; Bulte, Jeff W. M.

    2013-01-01

    Stem cell based-therapies are novel therapeutic strategies that hold key for developing new treatments for diseases conditions with very few or no cures. Although there has been an increase in the number of clinical trials involving stem cell-based therapies in the last few years, the long-term risks and benefits of these therapies are still unknown. Detailed in vivo studies are needed to monitor the fate of transplanted cells, including their distribution, differentiation, and longevity over time. Advancements in non-invasive cellular imaging techniques to track engrafted cells in real-time present a powerful tool for determining the efficacy of stem cell-based therapies. In this review, we describe the latest approaches to stem cell labeling and tracking using different imaging modalities. PMID:23975604

  2. Technology Advancement for Integrative Stem Cell Analyses

    PubMed Central

    Jeong, Yoon

    2014-01-01

    Scientists have endeavored to use stem cells for a variety of applications ranging from basic science research to translational medicine. Population-based characterization of such stem cells, while providing an important foundation to further development, often disregard the heterogeneity inherent among individual constituents within a given population. The population-based analysis and characterization of stem cells and the problems associated with such a blanket approach only underscore the need for the development of new analytical technology. In this article, we review current stem cell analytical technologies, along with the advantages and disadvantages of each, followed by applications of these technologies in the field of stem cells. Furthermore, while recent advances in micro/nano technology have led to a growth in the stem cell analytical field, underlying architectural concepts allow only for a vertical analytical approach, in which different desirable parameters are obtained from multiple individual experiments and there are many technical challenges that limit vertically integrated analytical tools. Therefore, we propose—by introducing a concept of vertical and horizontal approach—that there is the need of adequate methods to the integration of information, such that multiple descriptive parameters from a stem cell can be obtained from a single experiment. PMID:24874188

  3. Analytical strategies for studying stem cell metabolism

    PubMed Central

    Arnold, James M.; Choi, William T.; Sreekumar, Arun

    2015-01-01

    Owing to their capacity for self-renewal and pluripotency, stem cells possess untold potential for revolutionizing the field of regenerative medicine through the development of novel therapeutic strategies for treating cancer, diabetes, cardiovascular and neurodegenerative diseases. Central to developing these strategies is improving our understanding of biological mechanisms responsible for governing stem cell fate and self-renewal. Increasing attention is being given to the significance of metabolism, through the production of energy and generation of small molecules, as a critical regulator of stem cell functioning. Rapid advances in the field of metabolomics now allow for in-depth profiling of stem cells both in vitro and in vivo, providing a systems perspective on key metabolic and molecular pathways which influence stem cell biology. Understanding the analytical platforms and techniques that are currently used to study stem cell metabolomics, as well as how new insights can be derived from this knowledge, will accelerate new research in the field and improve future efforts to expand our understanding of the interplay between metabolism and stem cell biology. PMID:26213533

  4. Time to Reconsider Stem Cell Induction Strategies

    PubMed Central

    Denker, Hans-Werner

    2012-01-01

    Recent developments in stem cell research suggest that it may be time to reconsider the current focus of stem cell induction strategies. During the previous five years, approximately, the induction of pluripotency in somatic cells, i.e., the generation of so-called ‘induced pluripotent stem cells’ (iPSCs), has become the focus of ongoing research in many stem cell laboratories, because this technology promises to overcome limitations (both technical and ethical) seen in the production and use of embryonic stem cells (ESCs). A rapidly increasing number of publications suggest, however, that it is now possible to choose instead other, alternative ways of generating stem and progenitor cells bypassing pluripotency. These new strategies may offer important advantages with respect to ethics, as well as to safety considerations. The present communication discusses why these strategies may provide possibilities for an escape from the dilemma presented by pluripotent stem cells (self-organization potential, cloning by tetraploid complementation, patenting problems and tumor formation risk). PMID:24710555

  5. Technology advancement for integrative stem cell analyses.

    PubMed

    Jeong, Yoon; Choi, Jonghoon; Lee, Kwan Hyi

    2014-12-01

    Scientists have endeavored to use stem cells for a variety of applications ranging from basic science research to translational medicine. Population-based characterization of such stem cells, while providing an important foundation to further development, often disregard the heterogeneity inherent among individual constituents within a given population. The population-based analysis and characterization of stem cells and the problems associated with such a blanket approach only underscore the need for the development of new analytical technology. In this article, we review current stem cell analytical technologies, along with the advantages and disadvantages of each, followed by applications of these technologies in the field of stem cells. Furthermore, while recent advances in micro/nano technology have led to a growth in the stem cell analytical field, underlying architectural concepts allow only for a vertical analytical approach, in which different desirable parameters are obtained from multiple individual experiments and there are many technical challenges that limit vertically integrated analytical tools. Therefore, we propose--by introducing a concept of vertical and horizontal approach--that there is the need of adequate methods to the integration of information, such that multiple descriptive parameters from a stem cell can be obtained from a single experiment.

  6. Stem cell bioprocessing: fundamentals and principles

    PubMed Central

    Placzek, Mark R.; Chung, I-Ming; Macedo, Hugo M.; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Min Cha, Jae; Fauzi, Iliana; Kang, Yunyi; Yeo, David C.L.; Yip Joan Ma, Chi; Polak, Julia M.; Panoskaltsis, Nicki; Mantalaris, Athanasios

    2008-01-01

    In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the ‘omics’ technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical—failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications. PMID:19033137

  7. Adult Stem Cells and Diseases of Aging

    PubMed Central

    Boyette, Lisa B.; Tuan, Rocky S.

    2014-01-01

    Preservation of adult stem cells pools is critical for maintaining tissue homeostasis into old age. Exhaustion of adult stem cell pools as a result of deranged metabolic signaling, premature senescence as a response to oncogenic insults to the somatic genome, and other causes contribute to tissue degeneration with age. Both progeria, an extreme example of early-onset aging, and heritable longevity have provided avenues to study regulation of the aging program and its impact on adult stem cell compartments. In this review, we discuss recent findings concerning the effects of aging on stem cells, contributions of stem cells to age-related pathologies, examples of signaling pathways at work in these processes, and lessons about cellular aging gleaned from the development and refinement of cellular reprogramming technologies. We highlight emerging therapeutic approaches to manipulation of key signaling pathways corrupting or exhausting adult stem cells, as well as other approaches targeted at maintaining robust stem cell pools to extend not only lifespan but healthspan. PMID:24757526

  8. Stem cell bioprocessing: fundamentals and principles.

    PubMed

    Placzek, Mark R; Chung, I-Ming; Macedo, Hugo M; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Cha, Jae Min; Fauzi, Iliana; Kang, Yunyi; Yeo, David C L; Ma, Chi Yip Joan; Polak, Julia M; Panoskaltsis, Nicki; Mantalaris, Athanasios

    2009-03-01

    In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the 'omics' technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical-failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications.

  9. Hematopoietic stem cell mobilization: updated conceptual renditions

    PubMed Central

    Bonig, H; Papayannopoulou, T

    2013-01-01

    Despite its specific clinical relevance, the field of hematopoietic stem cell mobilization has received broad attention, owing mainly to the belief that pharmacologic stem cell mobilization might provide clues as to how stem cells are retained in their natural environment, the bone marrow ‘niche’. Inherent to this knowledge is also the desire to optimally engineer stem cells to interact with their target niche (such as after transplantation), or to lure malignant stem cells out of their protective niches (in order to kill them), and in general to decipher the niche’s structural components and its organization. Whereas, with the exception of the recent addition of CXCR4 antagonists to the armamentarium for mobilization of patients refractory to granulocyte colony-stimulating factor alone, clinical stem cell mobilization has not changed significantly over the last decade or so, much effort has been made trying to explain the complex mechanism(s) by which hematopoietic stem and progenitor cells leave the marrow. This brief review will report some of the more recent advances about mobilization, with an attempt to reconcile some of the seemingly inconsistent data in mobilization and to interject some commonalities among different mobilization regimes. PMID:22951944

  10. Cancer stem cells, cancer cell plasticity and radiation therapy.

    PubMed

    Vlashi, Erina; Pajonk, Frank

    2015-04-01

    Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms.

  11. Cancer Stem Cells, Cancer Cell Plasticity and Radiation Therapy

    PubMed Central

    Vlashi, Erina; Pajonk, Frank

    2014-01-01

    Summary Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms. PMID:25025713

  12. TOPICAL REVIEW: Stem cells engineering for cell-based therapy

    NASA Astrophysics Data System (ADS)

    Taupin, Philippe

    2007-09-01

    Stem cells carry the promise to cure a broad range of diseases and injuries, from diabetes, heart and muscular diseases, to neurological diseases, disorders and injuries. Significant progresses have been made in stem cell research over the past decade; the derivation of embryonic stem cells (ESCs) from human tissues, the development of cloning technology by somatic cell nuclear transfer (SCNT) and the confirmation that neurogenesis occurs in the adult mammalian brain and that neural stem cells (NSCs) reside in the adult central nervous system (CNS), including that of humans. Despite these advances, there may be decades before stem cell research will translate into therapy. Stem cell research is also subject to ethical and political debates, controversies and legislation, which slow its progress. Cell engineering has proven successful in bringing genetic research to therapy. In this review, I will review, in two examples, how investigators are applying cell engineering to stem cell biology to circumvent stem cells' ethical and political constraints and bolster stem cell research and therapy.

  13. Germline stem cells: origin and destiny.

    PubMed

    Lehmann, Ruth

    2012-06-14

    Germline stem cells are key to genome transmission to future generations. Over recent years, there have been numerous insights into the regulatory mechanisms that govern both germ cell specification and the maintenance of the germline in adults. Complex regulatory interactions with both the niche and the environment modulate germline stem cell function. This perspective highlights some examples of this regulation to illustrate the diversity and complexity of the mechanisms involved.

  14. Telomeres, stem cells, senescence, and cancer

    PubMed Central

    Sharpless, Norman E.; DePinho, Ronald A.

    2004-01-01

    Mammalian aging occurs in part because of a decline in the restorative capacity of tissue stem cells. These self-renewing cells are rendered malignant by a small number of oncogenic mutations, and overlapping tumor suppressor mechanisms (e.g., p16INK4a-Rb, ARF-p53, and the telomere) have evolved to ward against this possibility. These beneficial antitumor pathways, however, appear also to limit the stem cell life span, thereby contributing to aging. PMID:14722605

  15. Overexpression of Arabidopsis Ceramide Synthases Differentially Affects Growth, Sphingolipid Metabolism, Programmed Cell Death, and Mycotoxin Resistance.

    PubMed

    Luttgeharm, Kyle D; Chen, Ming; Mehra, Amit; Cahoon, Rebecca E; Markham, Jonathan E; Cahoon, Edgar B

    2015-10-01

    Ceramide synthases catalyze an N-acyltransferase reaction using fatty acyl-coenzyme A (CoA) and long-chain base (LCB) substrates to form the sphingolipid ceramide backbone and are targets for inhibition by the mycotoxin fumonisin B1 (FB1). Arabidopsis (Arabidopsis thaliana) contains three genes encoding ceramide synthases with distinct substrate specificities: LONGEVITY ASSURANCE GENE ONE HOMOLOG1 (LOH1; At3g25540)- and LOH3 (At1g19260)-encoded ceramide synthases use very-long-chain fatty acyl-CoA and trihydroxy LCB substrates, and LOH2 (At3g19260)-encoded ceramide synthase uses palmitoyl-CoA and dihydroxy LCB substrates. In this study, complementary DNAs for each gene were overexpressed to determine the role of individual isoforms in physiology and sphingolipid metabolism. Differences were observed in growth resulting from LOH1 and LOH3 overexpression compared with LOH2 overexpression. LOH1- and LOH3-overexpressing plants had enhanced biomass relative to wild-type plants, due in part to increased cell division, suggesting that enhanced synthesis of very-long-chain fatty acid/trihydroxy LCB ceramides promotes cell division and growth. Conversely, LOH2 overexpression resulted in dwarfing. LOH2 overexpression also resulted in the accumulation of sphingolipids with C16 fatty acid/dihydroxy LCB ceramides, constitutive induction of programmed cell death, and accumulation of salicylic acid, closely mimicking phenotypes observed previously in LCB C-4 hydroxylase mutants defective in trihydroxy LCB synthesis. In addition, LOH2- and LOH3-overexpressing plants acquired increased resistance to FB1, whereas LOH1-overexpressing plants showed no increase in FB1 resistance, compared with wild-type plants, indicating that LOH1 ceramide synthase is most strongly inhibited by FB1. Overall, the findings described here demonstrate that overexpression of Arabidopsis ceramide synthases results in strongly divergent physiological and metabolic phenotypes, some of which have significance

  16. S100A4 is frequently overexpressed in lung cancer cells and promotes cell growth and cell motility

    SciTech Connect

    Chen, Na; Sato, Daisuke; Saiki, Yuriko; Sunamura, Makoto; Fukushige, Shinichi; Horii, Akira

    2014-05-09

    Highlights: • We observed frequent overexpression of S100A4 in lung cancer cell lines. • Knockdown of S100A4 suppressed proliferation in lung cancer cells. • Forced expression of S100A4 accelerated cell motility in lung cancer cells. • PRDM2 was found to be one of the downstream suppressed genes of S100A4. - Abstract: S100A4, a small calcium-binding protein belonging to the S100 protein family, is commonly overexpressed in a variety of tumor types and is widely accepted to associate with metastasis by regulating the motility and invasiveness of cancer cells. However, its biological role in lung carcinogenesis is largely unknown. In this study, we found that S100A4 was frequently overexpressed in lung cancer cells, irrespective of histological subtype. Then we performed knockdown and forced expression of S100A4 in lung cancer cell lines and found that specific knockdown of S100A4 effectively suppressed cell proliferation only in lung cancer cells with S100A4-overexpression; forced expression of S100A4 accelerated cell motility only in S100A4 low-expressing lung cancer cells. PRDM2 and VASH1, identified as novel upregulated genes by microarray after specific knockdown of S100A4 in pancreatic cancer, were also analyzed, and we found that PRDM2 was significantly upregulated after S100A4-knockdown in one of two analyzed S100A4-overexpressing lung cancer cells. Our present results suggest that S100A4 plays an important role in lung carcinogenesis by means of cell proliferation and motility by a pathway similar to that in pancreatic cancer.

  17. RB mutation and RAS overexpression induce resistance to NK cell-mediated cytotoxicity in glioma cells.

    PubMed

    Orozco-Morales, Mario; Sánchez-García, Francisco Javier; Golán-Cancela, Irene; Hernández-Pedro, Norma; Costoya, Jose A; de la Cruz, Verónica Pérez; Moreno-Jiménez, Sergio; Sotelo, Julio; Pineda, Benjamín

    2015-01-01

    Several theories aim to explain the malignant transformation of cells, including the mutation of tumor suppressors and proto-oncogenes. Deletion of Rb (a tumor suppressor), overexpression of mutated Ras (a proto-oncogene), or both, are sufficient for in vitro gliomagenesis, and these genetic traits are associated with their proliferative capacity. An emerging hallmark of cancer is the ability of tumor cells to evade the immune system. Whether specific mutations are related with this, remains to be analyzed. To address this issue, three transformed glioma cell lines were obtained (Rb(-/-), Ras(V12), and Rb(-/-)/Ras(V12)) by in vitro retroviral transformation of astrocytes, as previously reported. In addition, Ras(V12) and Rb(-/-)/Ras(V12) transformed cells were injected into SCID mice and after tumor growth two stable glioma cell lines were derived. All these cells were characterized in terms of Rb and Ras gene expression, morphology, proliferative capacity, expression of MHC I, Rae1δ, and Rae1αβγδε, mult1, H60a, H60b, H60c, as ligands for NK cell receptors, and their susceptibility to NK cell-mediated cytotoxicity. Our results show that transformation of astrocytes (Rb loss, Ras overexpression, or both) induced phenotypical and functional changes associated with resistance to NK cell-mediated cytotoxicity. Moreover, the transfer of cell lines of transformed astrocytes into SCID mice increased resistance to NK cell-mediated cytotoxicity, thus suggesting that specific changes in a tumor suppressor (Rb) and a proto-oncogene (Ras) are enough to confer resistance to NK cell-mediated cytotoxicity in glioma cells and therefore provide some insight into the ability of tumor cells to evade immune responses.

  18. MicroRNAs: key regulators of stem cells.

    PubMed

    Gangaraju, Vamsi K; Lin, Haifan

    2009-02-01

    The hallmark of a stem cell is its ability to self-renew and to produce numerous differentiated cells. This unique property is controlled by dynamic interplays between extrinsic signalling, epigenetic, transcriptional and post-transcriptional regulations. Recent research indicates that microRNAs (miRNAs) have an important role in regulating stem cell self-renewal and differentiation by repressing the translation of selected mRNAs in stem cells and differentiating daughter cells. Such a role has been shown in embryonic stem cells, germline stem cells and various somatic tissue stem cells. These findings reveal a new dimension of gene regulation in controlling stem cell fate and behaviour. PMID:19165214

  19. Her-2 overexpression increases the metastatic outgrowth of breast cancer cells in the brain.

    PubMed

    Palmieri, Diane; Bronder, Julie L; Herring, Jeanne M; Yoneda, Toshiyuki; Weil, Robert J; Stark, Andreas M; Kurek, Raffael; Vega-Valle, Eleazar; Feigenbaum, Lionel; Halverson, Douglas; Vortmeyer, Alexander O; Steinberg, Seth M; Aldape, Kenneth; Steeg, Patricia S

    2007-05-01

    Retrospective studies of breast cancer patients suggest that primary tumor Her-2 overexpression or trastuzumab therapy is associated with a devastating complication: the development of central nervous system (brain) metastases. Herein, we present Her-2 expression trends from resected human brain metastases and data from an experimental brain metastasis assay, both indicative of a functional contribution of Her-2 to brain metastatic colonization. Of 124 archival resected brain metastases from breast cancer patients, 36.2% overexpressed Her-2, indicating an enrichment in the frequency of tumor Her-2 overexpression at this metastatic site. Using quantitative real-time PCR of laser capture microdissected epithelial cells, Her-2 and epidermal growth factor receptor (EGFR) mRNA levels in a cohort of 12 frozen brain metastases were increased up to 5- and 9-fold, respectively, over those of Her-2-amplified primary tumors. Co-overexpression of Her-2 and EGFR was also observed in a subset of brain metastases. We then tested the hypothesis that overexpression of Her-2 increases the colonization of breast cancer cells in the brain in vivo. A subclone of MDA-MB-231 human breast carcinoma cells that selectively metastasizes to brain (231-BR) overexpressed EGFR; 231-BR cells were transfected with low (4- to 8-fold) or high (22- to 28-fold) levels of Her-2. In vivo, in a model of brain metastasis, low or high Her-2-overexpressing 231-BR clones produced comparable numbers of micrometastases in the brain as control transfectants; however, the Her-2 transfectants yielded 3-fold greater large metastases (>50 microm(2); P < 0.001). Our data indicate that Her-2 overexpression increases the outgrowth of metastatic tumor cells in the brain in this model system. PMID:17483330

  20. Centre for human development, stem cells & regeneration.

    PubMed

    Oreffo, Richard O C

    2014-01-01

    The Centre for Human Development, Stem Cells and Regeneration (CHDSCR) was founded in 2004 as a cross-disciplinary research and translational program within the Faculty of Medicine at the University of Southampton. The Centre undertakes fundamental research into early development and stem cells together with applied translational research for patient benefit. The Centre has vibrant and thriving multidisciplinary research programs that harness the translational strength of the Faculty together with an innovative Stem Cell PhD program, outstanding clinical infrastructure and enterprise to deliver on this vision.

  1. Autologous Stem Cell Mobilization and Collection.

    PubMed

    Hsu, Yen-Michael S; Cushing, Melissa M

    2016-06-01

    Peripheral blood stem cell collection is an effective approach to obtain a hematopoietic graft for stem cell transplantation. Developing hematopoietic stem/progenitor cell (HSPC) mobilization methods and collection algorithms have improved efficiency, clinical outcomes, and cost effectiveness. Differences in mobilization mechanisms may change the HSPC content harvested and result in different engraftment kinetics and complications. Patient-specific factors can affect mobilization. Incorporating these factors in collection algorithms and improving assays for evaluating mobilization further extend the ability to obtain sufficient HSPCs for hematopoietic repopulation. Technological advance and innovations in leukapheresis have improved collection efficiency and reduced adverse effects. PMID:27112997

  2. Stem cell therapy in oral and maxillofacial region: An overview

    PubMed Central

    Sunil, PM; Manikandhan, R; Muthu, MS; Abraham, S

    2012-01-01

    Cells with unique capacity for self-renewal and potency are called stem cells. With appropriate biochemical signals stem cells can be transformed into desirable cells. The idea behind this article is to shortly review the obtained literature on stem cell with respect to their properties, types and advantages of dental stem cells. Emphasis has been given to the possibilities of stem cell therapy in the oral and maxillofacial region including regeneration of tooth and craniofacial defects. PMID:22434942

  3. Foxp1 maintains hair follicle stem cell quiescence through regulation of Fgf18

    PubMed Central

    Leishman, Erin; Howard, Jeffrey M.; Garcia, Gloria E.; Miao, Qi; Ku, Amy T.; Dekker, Joseph D.; Tucker, Haley; Nguyen, Hoang

    2013-01-01

    Hair follicles cyclically degenerate and regenerate throughout adult life and require regular stem cell activation to drive the cycle. In the resting phase of the hair cycle, hair follicle stem cells are maintained in a quiescent state until they receive signals to proliferate. We found that the forkhead transcription factor Foxp1 is crucial for maintaining the quiescence of hair follicle stem cells. Loss of Foxp1 in skin epithelial cells leads to precocious stem cell activation, resulting in drastic shortening of the quiescent phase of the hair cycle. Conversely, overexpression of Foxp1 in keratinocytes prevents cell proliferation by promoting cell cycle arrest. Finally, through both gain- and loss-of-function studies, we identify fibroblast growth factor 18 (Fgf18) as the key downstream target of Foxp1. We show that exogenously supplied FGF18 can prevent the hair follicle stem cells of Foxp1 null mice from being prematurely activated. As Fgf18 controls the length of the quiescent phase and is a key downstream target of Foxp1, our data strongly suggest that Foxp1 regulates the quiescent stem cell state in the hair follicle stem cell niche by controlling Fgf18 expression. PMID:23946441

  4. Overexpression of c-myc induces epithelial mesenchymal transition in mammary epithelial cells.

    PubMed

    Cho, Kyoung Bin; Cho, Min Kyong; Lee, Won Young; Kang, Keon Wook

    2010-07-28

    The c-myc gene is frequently overexpressed in human breast cancer and its target genes are involved in tumorigenesis. Epithelial mesenchymal transitions (EMT), where cells undergo a developmental switch from a polarized epithelial phenotype to a highly motile mesenchymal phenotype, are associated with invasion and motility of cancer cells. Basal E-cadherin expression was down-regulated in c-myc overexpressing MCF10A (c-myc-MCF10A) cells compared to GFP-overexpressing MCF10A (GFP-MCF10A) cells, while N-cadherin was distinctly increased in c-myc-MCF10A cells. Given that glycogen synthase kinase-3beta (GSK-3beta) and the snail axis have key roles in E-cadherin deregulation during EMT, we investigated the role of GSK-3beta/snail signaling pathways in the induction of EMT by c-myc overexpression. In contrast to GFP-MCF10A cells, both the transcriptional activity and the ubiquitination-dependent protein stability of snail were enhanced in c-myc-MCF10A cells, and this was reversed by GSK-3beta overexpression. We also found that c-myc overexpression inhibits GSK-3beta activity through activation of extracellular signal-regulated kinase (ERK). Inhibition of ERK by dominant negative mutant transfection or chemical inhibitor significantly suppressed snail gene transcription. These results suggest that c-myc overexpression during transformation of mammary epithelial cells (MEC) is involved in EMTs via ERK-dependent GSK-3beta inactivation and subsequent snail activation.

  5. Bioprinting and Differentiation of Stem Cells.

    PubMed

    Irvine, Scott A; Venkatraman, Subbu S

    2016-01-01

    The 3D bioprinting of stem cells directly into scaffolds offers great potential for the development of regenerative therapies; in particular for the fabrication of organ and tissue substitutes. For this to be achieved; the lineage fate of bioprinted stem cell must be controllable. Bioprinting can be neutral; allowing culture conditions to trigger differentiation or alternatively; the technique can be designed to be stimulatory. Such factors as the particular bioprinting technique; bioink polymers; polymer cross-linking mechanism; bioink additives; and mechanical properties are considered. In addition; it is discussed that the stimulation of stem cell differentiation by bioprinting may lead to the remodeling and modification of the scaffold over time matching the concept of 4D bioprinting. The ability to tune bioprinting properties as an approach to fabricate stem cell bearing scaffolds and to also harness the benefits of the cells multipotency is of considerable relevance to the field of biomaterials and bioengineering. PMID:27617991

  6. Cancer Stem Cells: Plasticity Works against Therapy

    PubMed Central

    Vinogradova, T. V.; Chernov, I. P.; Monastyrskaya, G. S.; Kondratyeva, L. G.; Sverdlov, E. D.

    2015-01-01

    Great successes in identification and deciphering of mechanisms of the adult stem cells regulation have given rise to the idea that stem cells can also function in tumors as central elements of their development, starting from the initial stage and continuing until metastasis. Such cells were called cancer stem cells (CSCs). Over the course of intense discussion, the CSCs hypothesis gradually began to be perceived as an obvious fact. Recently, the existence of CSCs has been indeed confirmed in a number of works. However, when are CSCs universal prerequisites of tumors and to what extent their role is essential for tumor evolution remains an issue far from resolved. Likewise, the problem of potential use of CSCs as therapeutic targets remains unsolved. The present review attempts to analyze the issue of cancer stem cells and the potential of targeting them in tumor therapy. PMID:26798491

  7. Stem Cell Research and Health Education.

    PubMed

    Eve, David J; Marty, Phillip J; McDermott, Robert J; Klasko, Stephen K; Sanberg, Paul R

    2008-01-01

    Stem cells are being touted as the greatest discovery for the potential treatment of a myriad of diseases in the new millennium, but there is still much research to be done before it will be known whether they can live up to this description. There is also an ethical debate over the production of one of the most valuable types of stem cell: the embryonic form. Consequently, there is public confusion over the benefits currently being derived from the use of stem cells and what can potentially be expected from their use in the future. The health educator's role is to give an unbiased account of the current state of stem cell research. This paper provides the groundwork by discussing the types of cells currently identified, their potential use, and some of the political and ethical pitfalls resulting from such use.

  8. Translational findings from cardiovascular stem cell research.

    PubMed

    Mazhari, Ramesh; Hare, Joshua M

    2012-01-01

    The possibility of using stem cells to regenerate damaged myocardium has been actively investigated since the late 1990s. Consistent with the traditional view that the heart is a "postmitotic" organ that possesses minimal capacity for self-repair, much of the preclinical and clinical work has focused exclusively on introducing stem cells into the heart, with the hope of differentiation of these cells into functioning cardiomyocytes. This approach is ongoing and retains promise but to date has yielded inconsistent successes. More recently, it has become widely appreciated that the heart possesses endogenous repair mechanisms that, if adequately stimulated, might regenerate damaged cardiac tissue from in situ cardiac stem cells. Accordingly, much recent work has focused on engaging and enhancing endogenous cardiac repair mechanisms. This article reviews the literature on stem cell-based myocardial regeneration, placing emphasis on the mutually enriching interaction between basic and clinical research.

  9. Translational Findings from Cardiovascular Stem Cell Research

    PubMed Central

    Mazhari, Ramesh; Hare, Joshua M

    2012-01-01

    The possibility of using stem cells to regenerate damaged myocardium has been actively investigated since the late 1990s. Consistent with the traditional view that the heart is a “post-mitotic” organ that possesses minimal capacity for self-repair, much of the preclinical and clinical work has focused exclusively on introducing stem cells into the heart, with the hope of differentiation of these cells into functioning cardiomyocytes. This approach is ongoing and retains promise but to date has yielded inconsistent successes. More recently, it has become widely appreciated that the heart possesses endogenous repair mechanisms that, if adequately stimulated, might regenerate damaged cardiac tissue from in situ cardiac stem cells. Accordingly, much recent work has focused on engaging and enhancing endogenous cardiac repair mechanisms. This article reviews the literature on stem-cell based myocardial regeneration, placing emphasis on the mutually enriching interaction between basic and clinical research. PMID:22940024

  10. HLA Engineering of Human Pluripotent Stem Cells

    PubMed Central

    Riolobos, Laura; Hirata, Roli K; Turtle, Cameron J; Wang, Pei-Rong; Gornalusse, German G; Zavajlevski, Maja; Riddell, Stanley R; Russell, David W

    2013-01-01

    The clinical use of human pluripotent stem cells and their derivatives is limited by the rejection of transplanted cells due to differences in their human leukocyte antigen (HLA) genes. This has led to the proposed use of histocompatible, patient-specific stem cells; however, the preparation of many different stem cell lines for clinical use is a daunting task. Here, we develop two distinct genetic engineering approaches that address this problem. First, we use a combination of gene targeting and mitotic recombination to derive HLA-homozygous embryonic stem cell (ESC) subclones from an HLA-heterozygous parental line. A small bank of HLA-homozygous stem cells with common haplotypes would match a significant proportion of the population. Second, we derive HLA class I–negative cells by targeted disruption of both alleles of the Beta-2 Microglobulin (B2M) gene in ESCs. Mixed leukocyte reactions and peptide-specific HLA-restricted CD8+ T cell responses were reduced in class I–negative cells that had undergone differentiation in embryoid bodies. These B2M−/− ESCs could act as universal donor cells in applications where the transplanted cells do not express HLA class II genes. Both approaches used adeno-associated virus (AAV) vectors for efficient gene targeting in the absence of potentially genotoxic nucleases, and produced pluripotent, transgene-free cell lines. PMID:23629003

  11. Crucial role of HMGA1 in the self-renewal and drug resistance of ovarian cancer stem cells.

    PubMed

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

    2016-01-01

    Cancer stem cells are a subpopulation of cancer cells characterized by self-renewal ability, tumorigenesis and drug resistance. The aim of this study was to investigate the role of HMGA1, a chromatin remodeling factor abundantly expressed in many different cancers, in the regulation of cancer stem cells in ovarian cancer. Spheroid-forming cancer stem cells were isolated from A2780, SKOV3 and PA1 ovarian cancer cells by three-dimensional spheroid culture. Elevated expression of HMGA1 was observed in spheroid cells along with increased expression of stemness-related genes, such as SOX2, KLF4, ALDH, ABCB1 and ABCG2. Furthermore, spheroid A2780 cells, compared with adherent cells, showed higher resistance to chemotherapeutic agents such as paclitaxel and doxorubicin. HMGA1 knockdown in spheroid cells reduced the proliferative advantage and spheroid-forming efficiency of the cells and the expression of stemness-related genes. HMGA1 overexpression in adherent A2780 cells increased cancer stem cell properties, including proliferation, spheroid-forming efficiency and the expression of stemness-related genes. In addition, HMGA1 regulated ABCG2 promoter activity through HMGA1-binding sites. Knockdown of HMGA1 in spheroid cells reduced resistance to chemotherapeutic agents, whereas the overexpression of HMGA1 in adherent ovarian cancer cells increased resistance to chemotherapeutic agents in vitro. Furthermore, HMGA1-overexpressing A2780 cells showed a significant survival advantage after chemotherapeutic agent treatment in a xenograft tumorigenicity assay. Together, our results provide novel insights regarding the critical role of HMGA1 in the regulation of the cancer stem cell characteristics of ovarian cancer cells, thus suggesting that HMGA1 may be an important target in the development of therapeutics for ovarian cancer patients. PMID:27561949

  12. Crucial role of HMGA1 in the self-renewal and drug resistance of ovarian cancer stem cells

    PubMed Central

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

    2016-01-01

    Cancer stem cells are a subpopulation of cancer cells characterized by self-renewal ability, tumorigenesis and drug resistance. The aim of this study was to investigate the role of HMGA1, a chromatin remodeling factor abundantly expressed in many different cancers, in the regulation of cancer stem cells in ovarian cancer. Spheroid-forming cancer stem cells were isolated from A2780, SKOV3 and PA1 ovarian cancer cells by three-dimensional spheroid culture. Elevated expression of HMGA1 was observed in spheroid cells along with increased expression of stemness-related genes, such as SOX2, KLF4, ALDH, ABCB1 and ABCG2. Furthermore, spheroid A2780 cells, compared with adherent cells, showed higher resistance to chemotherapeutic agents such as paclitaxel and doxorubicin. HMGA1 knockdown in spheroid cells reduced the proliferative advantage and spheroid-forming efficiency of the cells and the expression of stemness-related genes. HMGA1 overexpression in adherent A2780 cells increased cancer stem cell properties, including proliferation, spheroid-forming efficiency and the expression of stemness-related genes. In addition, HMGA1 regulated ABCG2 promoter activity through HMGA1-binding sites. Knockdown of HMGA1 in spheroid cells reduced resistance to chemotherapeutic agents, whereas the overexpression of HMGA1 in adherent ovarian cancer cells increased resistance to chemotherapeutic agents in vitro. Furthermore, HMGA1-overexpressing A2780 cells showed a significant survival advantage after chemotherapeutic agent treatment in a xenograft tumorigenicity assay. Together, our results provide novel insights regarding the critical role of HMGA1 in the regulation of the cancer stem cell characteristics of ovarian cancer cells, thus suggesting that HMGA1 may be an important target in the development of therapeutics for ovarian cancer patients. PMID:27561949

  13. Derivation of Neural Stem Cells from Mouse Induced Pluripotent Stem Cells.

    PubMed

    Karanfil, Işıl; Bagci-Onder, Tugba

    2016-01-01

    Neural stem cells (NSCs) derived from induced pluripotent stem cells offer therapeutic tools for neurodegenerative diseases. This review focuses on embryoid body (EB)-mediated stem cell culture techniques used to derive NSCs from mouse induced pluripotent stem cells (iPSCs). Generation of healthy and stable NSCs from iPSCs heavily depends on standardized in vitro cell culture systems that mimic the embryonic environments utilized during neural development. Specifically, the neural induction and expansion methods after EB formation are described in this review.

  14. The Androgen Receptor Bridges Stem Cell-Associated Signaling Nodes in Prostate Stem Cells

    PubMed Central

    Davies, Alastair H.; Zoubeidi, Amina

    2016-01-01

    The therapeutic potential of stem cells relies on dissecting the complex signaling networks that are thought to regulate their pluripotency and self-renewal. Until recently, attention has focused almost exclusively on a small set of “core” transcription factors for maintaining the stem cell state. It is now clear that stem cell regulatory networks are far more complex. In this review, we examine the role of the androgen receptor (AR) in coordinating interactions between signaling nodes that govern the balance of cell fate decisions in prostate stem cells. PMID:26880966

  15. Stem cells and somatic cells: reprogramming and plasticity.

    PubMed

    Estrov, Zeev

    2009-01-01

    Recent seminal discoveries have significantly advanced the field of stem cell research and received worldwide attention. Improvements in somatic cell nuclear transfer (SCNT) technology, enabling the cloning of Dolly the sheep, and the derivation and differentiation of human embryonic stem cells raised hopes that normal cells could be generated to replace diseased or injured tissue. At the same time, in vitro and in vivo studies demonstrated that somatic cells of one tissue are capable of generating cells of another tissue. It was theorized that any cell might be reprogrammed, by exposure to a new environment, to become another cell type. This concept contradicts two established hypotheses: (1) that only specific tissues are generated from the endoderm, mesoderm, and ectoderm and (2) that tissue cells arise from a rare population of tissue-specific stem cells in a hierarchical fashion. SCNT, cell fusion experiments, and most recent gene transfer studies also contradict these hypotheses, as they demonstrate that mature somatic cells can be reprogrammed to regain pluripotent (or even totipotent) stem cell capacity. On the basis of the stem cell theory, hierarchical cancer stem cell differentiation models have been proposed. Cancer cell plasticity is an established phenomenon that supports the notion that cellular phenotype and function might be altered. Therefore, mechanisms of cellular plasticity should be exploited and the clinical significance of the cancer stem cell theory cautiously assessed. PMID:19778860

  16. 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

  17. Neural Stem Cells and Ischemic Brain

    PubMed Central

    Zhang, Zhenggang; Chopp, Michael

    2016-01-01

    Stroke activates neural stem cells in the ventricular-subventricular zone (V/SVZ) of the lateral ventricle, which increases neuroblasts and oligodendrocyte progenitor cells (OPCs). Within the ischemic brain, neural stem cells, neuroblasts and OPCs appear to actively communicate with cerebral endothelial cells and other brain parenchymal cells to mediate ischemic brain repair; however, stroke-induced neurogenesis unlikely plays any significant roles in neuronal replacement. In this mini-review, we will discuss recent findings how intercellular communications between stroke-induced neurogenesis and oligodendrogenesis and brain parenchymal cells could potentially facilitate brain repair processes. PMID:27488979

  18. Hematopoietic stem cells: can old cells learn new tricks?

    PubMed

    Ho, Anthony D; Punzel, Michael

    2003-05-01

    Since the establishment of cell lines derived from human embryonic stem (ES) cells, it has been speculated that out of such "raw material," we could some day produce all sorts of replacement parts for the human body. Human pluripotent stem cells can be isolated from embryonic, fetal, or adult tissues. Enormous self-renewal capacity and developmental potential are the characteristics of ES cells. Somatic stem cells, especially those derived from hematopoietic tissues, have also been reported to exhibit developmental potential heretofore not considered possible. The initial evidences for the plasticity potential of somatic stem cells were so encouraging that the opponents of ES cell research used them as arguments for restricting ES cell research. In the past months, however, critical issues have been raised challenging the validity and the interpretation of the initial data. Whereas hematopoietic stem-cell therapy has been a clinical reality for almost 40 years, there is still a long way to go in basic research before novel therapy strategies with stem cells as replacement for other organ systems can be established. Given the present status, we should keep all options open for research in ES cells and adult stem cells to appreciate the complexity of their differentiation pathways and the relative merits of various types of stem cells for regenerative medicine. PMID:12714568

  19. Stem cell systems and regeneration in planaria.

    PubMed

    Rink, Jochen C

    2013-03-01

    Planarians are members of the Platyhelminthes (flatworms). These animals have evolved a remarkable stem cell system. A single pluripotent adult stem cell type ("neoblast") gives rise to the entire range of cell types and organs in the planarian body plan, including a brain, digestive-, excretory-, sensory- and reproductive systems. Neoblasts are abundantly present throughout the mesenchyme and divide continuously. The resulting stream of progenitors and turnover of differentiated cells drive the rapid self-renewal of the entire animal within a matter of weeks. Planarians grow and literally de-grow ("shrink") by the food supply-dependent adjustment of organismal turnover rates, scaling body plan proportions over as much as a 50-fold size range. Their dynamic body architecture further allows astonishing regenerative abilities, including the regeneration of complete and perfectly proportioned animals even from tiny tissue remnants. Planarians as an experimental system, therefore, provide unique opportunities for addressing a spectrum of current problems in stem cell research, including the evolutionary conservation of pluripotency, the dynamic organization of differentiation lineages and the mechanisms underlying organismal stem cell homeostasis. The first part of this review focuses on the molecular biology of neoblasts as pluripotent stem cells. The second part examines the fascinating mechanistic and conceptual challenges posed by a stem cell system that epitomizes a universal design principle of biological systems: the dynamic steady state.

  20. Adult Stem Cell Therapy for Stroke: Challenges and Progress

    PubMed Central

    Bang, Oh Young; Kim, Eun Hee; Cha, Jae Min; Moon, Gyeong Joon

    2016-01-01

    Stroke is one of the leading causes of death and physical disability among adults. It has been 15 years since clinical trials of stem cell therapy in patients with stroke have been conducted using adult stem cells like mesenchymal stem cells and bone marrow mononuclear cells. Results of randomized controlled trials showed that adult stem cell therapy was safe but its efficacy was modest, underscoring the need for new stem cell therapy strategies. The primary limitations of current stem cell therapies include (a) the limited source of engraftable stem cells, (b) the presence of optimal time window for stem cell therapies, (c) inherited limitation of stem cells in terms of growth, trophic support, and differentiation potential, and (d) possible transplanted cell-mediated adverse effects, such as tumor formation. Here, we discuss recent advances that overcome these hurdles in adult stem cell therapy for stroke. PMID:27733032

  1. A Short Review: Research progress of bovine stem cells.

    PubMed

    Gao, Y-H; Guan, W-J; Ma, Y-H

    2015-10-23

    All bodies rely on stem cells to grow from a single cell into an adult. Stem cells allow our bodies to build new tissue, such as new muscle when we exercise. Domestic livestock stem cells offer a unique opportunity to study developmental biology, serve as a resource to screen for harmful toxins or lifesaving drugs or even regenerative therapies for a number of diseases. This review provides information on bovine stem cells, emphasizing different sources of stem cells and current methods for isolation and culture of pluripotent stem cells from cattle. We also review the application of bovine stem cell in future.

  2. Tissue-specific designs of stem cell hierarchies.

    PubMed

    Visvader, Jane E; Clevers, Hans

    2016-04-01

    Recent work in the field of stem cell biology suggests that there is no single design for an adult tissue stem cell hierarchy, and that different tissues employ distinct strategies to meet their self-renewal and repair requirements. Stem cells may be multipotent or unipotent, and can exist in quiescent or actively dividing states. 'Professional' stem cells may also co-exist with facultative stem cells, which are more specialized daughter cells that revert to a stem cell state under specific tissue damage conditions. Here, we discuss stem cell strategies as seen in three solid mammalian tissues: the intestine, mammary gland and skeletal muscle. PMID:26999737

  3. Cancer stem cell targeted therapy: progress amid controversies

    PubMed Central

    Wang, Tao; Shigdar, Sarah; Gantier, Michael P.; Hou, Yingchun; Wang, Li; Li, Yong; Shamaileh, Hadi Al; Yin, Wang; Zhou, Shu-Feng; Zhao, Xinhan; Duan, Wei

    2015-01-01

    Although cancer stem cells have been well characterized in numerous malignancies, the fundamental characteristics of this group of cells, however, have been challenged by some recent observations: cancer stem cells may not necessary to be rare within tumors; cancer stem cells and non-cancer stem cells may undergo reversible phenotypic changes; and the cancer stem cells phenotype can vary substantially between patients. Here the current status and progresses of cancer stem cells theory is illustrated and via providing a panoramic view of cancer therapy, we addressed the recent controversies regarding the feasibility of cancer stem cells targeted anti-cancer therapy. PMID:26496035

  4. [Overexpression of KIAA1456 inhibits the proliferation of HO8910PM cells].

    PubMed

    Chen, Huaimei; Wang, Jia; Zhang, Yingfeng; Gao, Yanhong

    2016-09-01

    Objective To investigate the effect of over-expressed KIAA1456 on the proliferation and cell cycle of HO8910PM cells. Methods KIAA1456 was amplified by PCR and inserted into lentiviral expression vector Ubi-MCS-EGFP-IRES-puromycin to construct Ubi-KIAA1456-EGFP-puromycin (LV-KIAA1456) vector. Thereafter, the lentiviral particles were packaged and used to infect HO8910PM cells. The green fluorescence protein (GFP) expression was observed at 72 hours. The expression of KIAA1456 was examined by reverse transcription PCR and Western blotting. Cell growth was detected with CCK-8 assay and cell cycles were analyzed by flow cytometry. Results Reverse transcription PCR and Western blotting showed that HO8910PM cells infected with LV-KIAA1456 vector over-expressed KIAA1456 mRNA and protein. Cell proliferation was inhibited and G1 phase cells significantly increased in HO8910PM cells overexpressing KIAA1456. Conclusion Over-expression of KIAA1456 inhibits the proliferation of HO8910PM ovarian cancer cells and arrests the cell cycle in G1 phase. PMID:27609572

  5. Effects of resistin-like molecule β over-expression on gastric cancer cells in vitro

    PubMed Central

    Zheng, Li-Duan; Yang, Chun-Lei; Qi, Teng; Qi, Meng; Tong, Ling; Tong, Qiang-Song

    2012-01-01

    AIM: To investigate the effects of resistin-like molecule β (RELMβ) over-expression on the invasion, metastasis and angiogenesis of gastric cancer cells. METHODS: Human RELMβ encoding expression vector was constructed and transfected into the RELMβ lowly-expressed gastric cancer cell lines SGC-7901 and MKN-45. Gene expression was measured by Western blotting, reverse transcription polymerase chain reaction (PCR) and real-time quantitative PCR. Cell proliferation was measured by 2-(4,5-dimethyltriazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetry, colony formation and 5-ethynyl-20-deoxyuridine incorporation assays. The in vitro migration, invasion and metastasis of cancer cells were measured by cell adhesion assay, scratch assay and matrigel invasion assay. The angiogenic capabilities of cancer cells were measured by tube formation of endothelial cells. RESULTS: Transfection of RELMβ vector into SGC-7901 and MKN-45 cells resulted in over-expression of RELMβ, which did not influence the cellular proliferation. However, over-expression of RELMβ suppressed the in vitro adhesion, invasion and metastasis of cancer cells, accompanied by decreased expression of matrix metalloproteinase-2 (MMP-2) and MMP-9. Moreover, transfection of RELMβ attenuated the expression of vascular endothelial growth factor and in vitro angiogenic capabilities of cancer cells. CONCLUSION: Over-expression of RELMβ abolishes the invasion, metastasis and angiogenesis of gastric cancer cells in vitro, suggesting its potentials as a novel therapeutic target for gastric cancer. PMID:22371635

  6. Role of liver stem cells in hepatocarcinogenesis

    PubMed Central

    Xu, Lei-Bo; Liu, Chao

    2014-01-01

    Liver cancer is an aggressive disease with a high mortality rate. Management of liver cancer is strongly dependent on the tumor stage and underlying liver disease. Unfortunately, most cases are discovered when the cancer is already advanced, missing the opportunity for surgical resection. Thus, an improved understanding of the mechanisms responsible for liver cancer initiation and progression will facilitate the detection of more reliable tumor markers and the development of new small molecules for targeted therapy of liver cancer. Recently, there is increasing evidence for the “cancer stem cell hypothesis”, which postulates that liver cancer originates from the malignant transformation of liver stem/progenitor ce