A CDC20-APC/SOX2 Signaling Axis Regulates Human Glioblastoma Stem-like Cells. Mao, DD; Gujar, AD; Mahlokozera, T; Chen, I; Pan, Y; Luo, J; Brost, T; Thompson, EA; Turski, A; Leuthardt, EC; Dunn, GP; Chicoine, MR; Rich, KM; Dowling, JL; Zipfel, GJ; Dacey, RG; Achilefu, S; Tran, DD; Yano, H; Kim, AH Cell reports
1809-21
2015
Show Abstract
Glioblastoma harbors a dynamic subpopulation of glioblastoma stem-like cells (GSCs) that can propagate tumors in vivo and is resistant to standard chemoradiation. Identification of the cell-intrinsic mechanisms governing this clinically important cell state may lead to the discovery of therapeutic strategies for this challenging malignancy. Here, we demonstrate that the mitotic E3 ubiquitin ligase CDC20-anaphase-promoting complex (CDC20-APC) drives invasiveness and self-renewal in patient tumor-derived GSCs. Moreover, CDC20 knockdown inhibited and CDC20 overexpression increased the ability of human GSCs to generate brain tumors in an orthotopic xenograft model in vivo. CDC20-APC control of GSC invasion and self-renewal operates through pluripotency-related transcription factor SOX2. Our results identify a CDC20-APC/SOX2 signaling axis that controls key biological properties of GSCs, with implications for CDC20-APC-targeted strategies in the treatment of glioblastoma. | Immunoblotting (Western), Chromatin Immunoprecipitation (ChIP) | 26074073
|
Glial cell line-derived neurotrophic factor-secreting human neural progenitors show long-term survival, maturation into astrocytes, and no tumor formation following transplantation into the spinal cord of immunocompromised rats. Gowing, G; Shelley, B; Staggenborg, K; Hurley, A; Avalos, P; Victoroff, J; Latter, J; Garcia, L; Svendsen, CN Neuroreport
25
367-72
2014
Show Abstract
Human neural progenitor cells (hNPCs) derived from the fetal cortex can be expanded in vitro and genetically modified through lentiviral transduction to secrete growth factors shown to have a neurotrophic effect in animal models of neurological disease. hNPCs survive and mature following transplantation into the central nervous system of large and small animals including the rat model of amyotrophic lateral sclerosis. Here we report that hNPCs engineered to express glial cell line-derived neurotrophic factor (GDNF) survive long-term (7.5 months) following transplantation into the spinal cord of athymic nude rats and continue to secrete GDNF. Cell proliferation declined while the number of astrocytes increased, suggesting final maturation of the cells over time in vivo. Together these data show that GDNF-producing hNPCs may be useful as a source of cells for long-term delivery of both astrocytes and GDNF to the damaged central nervous system. | Immunohistochemistry | 24284956
|
Mesenchymal stem cells enhance autophagy and increase β-amyloid clearance in Alzheimer disease models. Shin, JY; Park, HJ; Kim, HN; Oh, SH; Bae, JS; Ha, HJ; Lee, PH Autophagy
32-44
2014
Show Abstract
Current evidence suggests a central role for autophagy in Alzheimer disease (AD), and dysfunction in the autophagic system may lead to amyloid-β (Aβ) accumulation. Using in vitro and in vivo AD models, the present study investigated whether mesenchymal stem cells (MSCs) could enhance autophagy and thus exert a neuroprotective effect through modulation of Aβ clearance In Aβ-treated neuronal cells, MSCs increased cellular viability and enhanced LC3-II expression compared with cells treated with Aβ only. Immunofluorescence revealed that MSC coculture in Aβ-treated neuronal cells increased the number of LC3-II-positive autophagosomes that were colocalized with a lysosomal marker. Ultrastructural analysis revealed that most autophagic vacuoles (AVs) in Aβ-treated cells were not fused with lysosomes, whereas a large portion of autophagosomes were conjoined with lysosomes in MSCs cocultured with Aβ-treated neuronal cells. Furthermore, MSC coculture markedly increased Aβ immunoreactivity colocalized within lysosomes and decreased intracellular Aβ levels compared with Aβ-treated cells. In Aβ-treated animals, MSC administration significantly increased autophagosome induction, final maturation of late AVs, and fusion with lysosomes. Moreover, MSC administration significantly reduced the level of Aβ in the hippocampus, which was elevated in Aβ-treated mice, concomitant with increased survival of hippocampal neurons. Finally, MSC coculture upregulated BECN1/Beclin 1 expression in AD models. These results suggest that MSCs significantly enhance autolysosome formation and clearance of Aβ in AD models, which may lead to increased neuronal survival against Aβ toxicity. Modulation of the autophagy pathway to repair the damaged AD brain using MSCs would have a significant impact on future strategies for AD treatment. | ChIP-seq | 24149893
|
Functional role of CLIC1 ion channel in glioblastoma-derived stem/progenitor cells. Setti, M; Savalli, N; Osti, D; Richichi, C; Angelini, M; Brescia, P; Fornasari, L; Carro, MS; Mazzanti, M; Pelicci, G Journal of the National Cancer Institute
105
1644-55
2013
Show Abstract
Chloride channels are physiologically involved in cell division and motility. Chloride intracellular channel 1 (CLIC1) is overexpressed in a variety of human solid tumors compared with normal tissues, suggesting a potential involvement of CLIC1 in the regulation of tumorigenesis. This led us to investigate the role of CLIC1 in gliomagenesis.We used the neurosphere system to isolate stem/progenitor cells from human glioblastomas (GBMs). CLIC1 targeting in GBM neurospheres was achieved by both lentiviral-mediated short-hairpin RNA transduction and CLIC1 antibody treatment, and its effect on stem-like properties was analyzed in vitro by proliferation and clonogenic assays and in vivo by orthotopic injection in immunocompromised mice. Channel activity was studied by perforated patch clamp technique. Differences in expression were analyzed by analysis of variance with Tamhane's multiple comparison test. Kaplan-Meier analyses and log-rank test were used to assess survival. All statistical tests were two-sided.CLIC1 was statistically significantly overexpressed in GBMs compared with normal brain tissues (P less than .001) with a better survival of patients with CLIC1 low-expressing tumors (CLIC1(low) vs CLIC1(high) survival: χ(2) = 74.35; degrees of freedom = 1; log-rank P less than .001). CLIC1 was variably expressed in patient-derived GBM neurospheres and was found enriched in the stem/progenitor compartment. CLIC1 silencing reduced proliferative (P less than .01), clonogenic (P less than .01), and tumorigenic capacity (P less than .05) of stem/progenitor cells. The reduction of CLIC1 chloride currents with a specific CLIC1 antibody mirrored the biological effects of CLIC1 silencing in GBM patient-derived neurospheres.Reduced gliomagenesis after CLIC1 targeting in tumoral stem/progenitor cells and the finding that CLIC1 expression is inversely associated with patient survival suggest CLIC1 as a potential target and prognostic biomarker. | | 24115360
|
Intraspinal transplantation of mouse and human neural precursor cells. Weinger, JG; Chen, L; Coleman, R; Leang, R; Plaisted, WC; Loring, JF; Lane, TE Current protocols in stem cell biology
26
Unit 2D.16.
2013
Show Abstract
This unit describes the preparation and transplantation of human neural precursor cells (hNPCs) and mouse neural precursor cells (mNPCs) into the thoracic region of the mouse spinal cord. The techniques in this unit also describe how to prepare the mouse for surgery by performing a laminectomy to expose the spinal cord for transplantation. NPCs genetically labeled with eGFP transplanted into the spinal cord of a mouse following viral-mediated demyelination can efficiently be detected via eGFP expression. Transplantation of these cells into the spinal cord is an efficacious way to determine their effects in neurological disorders such as multiple sclerosis, Alzheimer's disease, and spinal cord injury. | | 24510791
|