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7. Hes3 regulates cell number in cultures from glioblastoma multiforme with stem cell characteristics

Author

Park, Deric M., Jung, Jinkyu, Masjkur, Jimmy, Makrogkikas, Stylianos, Ebermann, Doreen, Saha, Sarama, Rogliano, Roberta, Paolillo, Nicoletta, Pacioni, Simone, McKay, Ron D., Poser, Steve, and Androutsellis-Theotokis, Andreas

Subjects
STAT3 Transcription Factor, Epidermal Growth Factor, Janus Kinase 1, Neural stem cells, Cancer stem cells, Stem-cell research, CNS cancer, Technical University Dresden, Publication funds, Article, Angiopoietin-2, Central Nervous System Neoplasms, DNA-Binding Proteins, Repressor Proteins, Mice, Neurale Stammzellen, Krebsstammzellen, Stammzellenforschung, zentrales Nervensystem, TU Dresden, Publikationsfonds, Neoplastic Stem Cells, Tumor Cells, Cultured, Animals, Fibroblast Growth Factor 2, ddc:610, Phosphorylation, RNA, Small Interfering, Glioblastoma, Biomarkers, Embryonic Stem Cells, Transcription Factors
Abstract

Tumors exhibit complex organization and contain a variety of cell populations. The realization that the regenerative properties of a tumor may be largely confined to a cell subpopulation (cancer stem cell) is driving a new era of anti-cancer research. Cancer stem cells from Glioblastoma Multiforme tumors express markers that are also expressed in non-cancerous neural stem cells, including nestin and Sox2. We previously showed that the transcription factor Hes3 is a marker of neural stem cells, and that its expression is inhibited by JAK activity. Here we show that Hes3 is also expressed in cultures from glioblastoma multiforme which express neural stem cell markers, can differentiate into neurons and glia, and can recapitulate the tumor of origin when transplanted into immunocompromised mice. Similar to observations in neural stem cells, JAK inhibits Hes3 expression. Hes3 RNA interference reduces the number of cultured glioblastoma cells suggesting a novel therapeutic strategy.

Published
2013

8. Androutsellis-Theotokis, A. et al. Notch signalling regulates stem cell numbers in vitro and in vivo. Nature 442, 823-826

Author

Androutsellis-Theotokis, Andreas, Leker, Ronen R., Soldner, Frank, Hoeppner, Daniel J., Ravin, Rea, Poser, Steve W., Rueger, Maria A., Bae, Soo-Kyung, Kittappa, Raja, and McKay, Ronald D. G.

Abstract

The hope of developing new transplantation therapies for degenerative diseases is limited by inefficient stem cell growth and immunological incompatibility with the host. Here we show that Notch receptor activation induces the expression of the specific target genes hairy and enhancer of split 3 (Hes3) and Sonic hedgehog (Shh) through rapid activation of cytoplasmic signals, including the serine/threonine kinase Akt, the transcription factor STAT3 and mammalian target of rapamycin, and thereby promotes the survival of neural stem cells. In both murine somatic and human embryonic stem cells, these positive signals are opposed by a control mechanism that involves the p38 mitogen-activated protein kinase. Transient administration of Notch ligands to the brain of adult rats increases the numbers of newly generated precursor cells and improves motor skills after ischaemic injury. These data indicate that stem cell expansion in vitro and in vivo, two central goals of regenerative medicine, may be achieved by Notch ligands through a pathway that is fundamental to development and cancer.

Published
2006

9. A Defined, Controlled Culture System for Primary Bovine Chromaffin Progenitors Reveals Novel Biomarkers and Modulators

Author

Masjkur, Jimmy, primary, Levenfus, Ian, additional, Lange, Sven, additional, Arps-Forker, Carina, additional, Poser, Steve, additional, Qin, Nan, additional, Vukicevic, Vladimir, additional, Chavakis, Triantafyllos, additional, Eisenhofer, Graeme, additional, Bornstein, Stefan R., additional, Ehrhart-Bornstein, Monika, additional, and Androutsellis-Theotokis, Andreas, additional

Published
2014
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10. Hes3 regulates cell number in cultures from glioblastoma multiforme with stem cell characteristics

Author

Park, Deric M., primary, Jung, Jinkyu, additional, Masjkur, Jimmy, additional, Makrogkikas, Stylianos, additional, Ebermann, Doreen, additional, Saha, Sarama, additional, Rogliano, Roberta, additional, Paolillo, Nicoletta, additional, Pacioni, Simone, additional, McKay, Ron D., additional, Poser, Steve, additional, and Androutsellis-Theotokis, Andreas, additional

Published
2013
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15. Targeting neural precursors in the adult brain rescues injured dopamine neurons.

Author

AndroutseIlis-Theotokis, Andreas, Rueger, Maria A., Park, Deric M., Mkhikian, Haik, Korb, Erica, Poser, Steve W., Walbridge, Stuart, Munasinghe, Jeeva, Koretsky, Alan P., Lonser, Russel R., and McKay, Ronald D.

Subjects
DOPAMINERGIC neurons, DOPAMINERGIC mechanisms, NEURONS, PARKINSON'S disease, EXTRAPYRAMIDAL disorders, BRAIN diseases
Abstract

In Parkinson's disease, multiple cell types in many brain regions are afflicted. As a consequence, a therapeutic strategy that activates a general neuroprotective response may be valuable. We have previously shown that Notch ligands support neural precursor cells in vitro and in vivo. Here we show that neural precursors express the angiopoietin receptor Tie2 and that injections of angiopoietin2 activate precursors in the adult brain. Signaling downstream of Tie2 and the Notch receptor regulate blood vessel formation. In the adult brain, angiopoietin2 and the Notch ligand Dll4 activate neural precursors with opposing effects on the density of blood vessels. A model of Parkinson's disease was used to show that angiopoietin2 and Dll4 rescue injured dopamine neurons with motor behavioral improvement. A combination of growth factors with little impact on the vasculature retains the ability to stimulate neural precursors and protect dopamine neurons. The cellular and pharmacological basis of the neuroprotective effects achieved by these single treatments merits further analysis. [ABSTRACT FROM AUTHOR]

Published
2009
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16. A Novel Role For Serum Response Factor in Neuronal Survival.

Author

Chang, Sandra H., Poser, Steve, and Zhengui Xia

Subjects
*NEUROTROPHINS, *NEURAL development, *APOPTOSIS, *NEURONS, *GENETIC transcription, *GENE expression
Abstract

Recent studies indicate that neuroprotection afforded by brain-derived neurotrophic factor (BDNF) is mediated by extracellular signalregulated kinase (ERK) and phosphatidylinositol-3 kinase (PI3K). However, the mechanisms by which ERK and PI3K exert neuroprotection are not completely understood. Because ERK1/2 and PI3K both stimulate serum response element (SRE)-mediated gene expression, and serum response factor (SRF) is indispensable for SRE-mediated transcription, we investigated whether SRF contributes to ERK1/2 and PI3K neuroprotection. To accomplish this goal, we used an established experimental paradigm in which BDNF protects postnatal cortical neurons against both trophic deprivation and camptothecin-induced DNA damage. BDNF protection against camptothecin is mediated primarily by ERK1/2 activation, whereas its protection against trophic deprivation is mainly through stimulation of the PI3K pathway (Hetman et al., 1999). Here we demonstrate that expression of a wild-type SRF is sufficient to protect postnatal cortical neurons against camptothecin or trophic deprivation. Expression of a dominant-negative SRF partially reversed BDNF neuroprotection against both apoptotic insults. Moreover, the dominant-negative SRF inhibited neuroprotection against trophic withdrawal afforded by expression of a constitutive active PI3K. In addition, protection against camptothecin by expression of constitutive active mitogen-activated protein kinase kinase 1, an upstream kinase that activates ERK1/2, was also blocked by expression of the dominant-negative SRF. These data suggest that SRF is both necessary and sufficient for BDNF neuroprotection of cortical neurons against trophic deprivation and DNA damage. Our data provide a direct demonstration of a biological function of SRF in neurons and a novel downstream neuroprotective mechanism common to both ERK1/2 and PI3K pathways. [ABSTRACT FROM AUTHOR]

Published
2004
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18. A defined, controlled culture system for primary bovine chromaffin progenitors reveals novel biomarkers and modulators

Author

Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, Androutsellis-Theotokis, Andreas, Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, and Androutsellis-Theotokis, Andreas

Abstract

We present a method to efficiently culture primary chromaffin progenitors from the adult bovine adrenal medulla in a defined, serum-free monolayer system. Tissue is dissociated and plated for expansion under support by the mitogen basic fibroblast growth factor (bFGF). The cultures, although not homogenous, contain a subpopulation of cells expressing the neural stem cell marker Hes3 that also propagate. In addition, Hes3 is also expressed in the adult adrenal medulla from where the tissue is taken. Differentiation is induced by bFGF withdrawal and switching to Neurobasal medium containing B27. Following differentiation, Hes3 expression is lost, and cells acquire morphologies and biomarker expression patterns of chromaffin cells and dopaminergic neurons. We tested the effect of different treatments that we previously showed regulate Hes3 expression and cell number in cultures of fetal and adult rodent neural stem cells. Treatment of the cultures with a combination of Delta4, Angiopoietin2, and a Janus kinase inhibitor increases cell number during the expansion phase without significantly affecting catecholamine content levels. Treatment with cholera toxin does not significantly affect cell number but reduces the ratio of epinephrine to norepinephrine content and increases the dopamine content relative to total catecholamines. These data suggest that this defined culture system can be used for target identification in drug discovery programs and that the transcription factor Hes3 may serve as a new biomarker of putative adrenomedullary chromaffin progenitor cells.

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19. A defined, controlled culture system for primary bovine chromaffin progenitors reveals novel biomarkers and modulators

Author

Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, Androutsellis-Theotokis, Andreas, Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, and Androutsellis-Theotokis, Andreas

Abstract

We present a method to efficiently culture primary chromaffin progenitors from the adult bovine adrenal medulla in a defined, serum-free monolayer system. Tissue is dissociated and plated for expansion under support by the mitogen basic fibroblast growth factor (bFGF). The cultures, although not homogenous, contain a subpopulation of cells expressing the neural stem cell marker Hes3 that also propagate. In addition, Hes3 is also expressed in the adult adrenal medulla from where the tissue is taken. Differentiation is induced by bFGF withdrawal and switching to Neurobasal medium containing B27. Following differentiation, Hes3 expression is lost, and cells acquire morphologies and biomarker expression patterns of chromaffin cells and dopaminergic neurons. We tested the effect of different treatments that we previously showed regulate Hes3 expression and cell number in cultures of fetal and adult rodent neural stem cells. Treatment of the cultures with a combination of Delta4, Angiopoietin2, and a Janus kinase inhibitor increases cell number during the expansion phase without significantly affecting catecholamine content levels. Treatment with cholera toxin does not significantly affect cell number but reduces the ratio of epinephrine to norepinephrine content and increases the dopamine content relative to total catecholamines. These data suggest that this defined culture system can be used for target identification in drug discovery programs and that the transcription factor Hes3 may serve as a new biomarker of putative adrenomedullary chromaffin progenitor cells.

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20. A defined, controlled culture system for primary bovine chromaffin progenitors reveals novel biomarkers and modulators

Author

Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, Androutsellis-Theotokis, Andreas, Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, and Androutsellis-Theotokis, Andreas

Abstract

We present a method to efficiently culture primary chromaffin progenitors from the adult bovine adrenal medulla in a defined, serum-free monolayer system. Tissue is dissociated and plated for expansion under support by the mitogen basic fibroblast growth factor (bFGF). The cultures, although not homogenous, contain a subpopulation of cells expressing the neural stem cell marker Hes3 that also propagate. In addition, Hes3 is also expressed in the adult adrenal medulla from where the tissue is taken. Differentiation is induced by bFGF withdrawal and switching to Neurobasal medium containing B27. Following differentiation, Hes3 expression is lost, and cells acquire morphologies and biomarker expression patterns of chromaffin cells and dopaminergic neurons. We tested the effect of different treatments that we previously showed regulate Hes3 expression and cell number in cultures of fetal and adult rodent neural stem cells. Treatment of the cultures with a combination of Delta4, Angiopoietin2, and a Janus kinase inhibitor increases cell number during the expansion phase without significantly affecting catecholamine content levels. Treatment with cholera toxin does not significantly affect cell number but reduces the ratio of epinephrine to norepinephrine content and increases the dopamine content relative to total catecholamines. These data suggest that this defined culture system can be used for target identification in drug discovery programs and that the transcription factor Hes3 may serve as a new biomarker of putative adrenomedullary chromaffin progenitor cells.

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21. A defined, controlled culture system for primary bovine chromaffin progenitors reveals novel biomarkers and modulators

Author

Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, Androutsellis-Theotokis, Andreas, Masjkur, Jimmy, Levenfus, Ian, Lange, Sven, Arps-Forker, Carina, Poser, Steve, Qin, Nan, Vukicevic, Vladimir, Chavakis, Triantafyllos, Eisenhofer, Graeme, Bornstein, Stefan R., Ehrhart-Bornstein, Monika, and Androutsellis-Theotokis, Andreas

Abstract

We present a method to efficiently culture primary chromaffin progenitors from the adult bovine adrenal medulla in a defined, serum-free monolayer system. Tissue is dissociated and plated for expansion under support by the mitogen basic fibroblast growth factor (bFGF). The cultures, although not homogenous, contain a subpopulation of cells expressing the neural stem cell marker Hes3 that also propagate. In addition, Hes3 is also expressed in the adult adrenal medulla from where the tissue is taken. Differentiation is induced by bFGF withdrawal and switching to Neurobasal medium containing B27. Following differentiation, Hes3 expression is lost, and cells acquire morphologies and biomarker expression patterns of chromaffin cells and dopaminergic neurons. We tested the effect of different treatments that we previously showed regulate Hes3 expression and cell number in cultures of fetal and adult rodent neural stem cells. Treatment of the cultures with a combination of Delta4, Angiopoietin2, and a Janus kinase inhibitor increases cell number during the expansion phase without significantly affecting catecholamine content levels. Treatment with cholera toxin does not significantly affect cell number but reduces the ratio of epinephrine to norepinephrine content and increases the dopamine content relative to total catecholamines. These data suggest that this defined culture system can be used for target identification in drug discovery programs and that the transcription factor Hes3 may serve as a new biomarker of putative adrenomedullary chromaffin progenitor cells.

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