title: Gliosarcoma stem cells undergo glial and mesenchymal differentiation in vivo.
abstract: Cancer stem cells (CSCs) are characterized by their self-renewing potential and by their ability to differentiate and phenocopy the original tumor in orthotopic xenografts. Long-term propagation of glioblastoma (GBM) cells in serum-containing medium results in loss of the CSCs and outgrowth of cells genetically and biologically divergent from the parental tumors. In contrast, the use of a neurosphere assay, a serum-free culture for selection, and propagation of central nervous system-derived stem cells allows the selection of a subpopulation containing CSCs. Gliosarcoma (GS), a morphological variant comprising approximately 2% of GBMs, present a biphasic growth pattern, composed of glial and metaplastic mesenchymal components. To assess whether the neurosphere assay would allow the amplification of a subpopulation of cells with "gliosarcoma stem cell" properties, capable of propagating both components of this malignancy, we have generated neurospheres and serum cultures from primary GS and GBM surgical specimens. Neurosphere cultures from GBM and GS samples expressed neural stem cell markers Sox2, Musashi1, and Nestin. In contrast to the GBM neurosphere lines, the GS neurospheres were negative for the stem cell marker CD133. All neurosphere lines generated high-grade invasive orthotopic tumor xenografts, with histological features strikingly similar to the parental tumors, demonstrating that these cultures indeed are enriched in CSCs. Remarkably, low-passage GS serum cultures retained the expression of stem cell markers, the ability to form neurospheres, and tumorigenicity. The GS experimental tumors phenocopied the parental tumor, exhibiting biphasic glial and mesenchymal components, constituting a clinically relevant model to investigate mesenchymal differentiation in GBMs.
authors: Department of Neurosurgery, Henry Ford Hospital, Detroit, Michigan 48202-2689, USA. ana@neuro.hfh.edu
authors: Ana C
authors: AC
authors: deCarvalho
authors: Kevin
authors: K
authors: Nelson
authors: Nancy
authors: N
authors: Lemke
authors: Norman L
authors: NL
authors: Lehman
authors: Ali S
authors: AS
authors: Arbab
authors: Steven
authors: S
authors: Kalkanis
authors: Tom
authors: T
authors: Mikkelsen
mesh_terms: D000071916:AC133 Antigen; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D015153:Blotting, Western; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology*; D005909:Glioblastoma / Q000378:metabolism / Q000473:pathology*; D018316:Gliosarcoma / Q000378:metabolism / Q000473:pathology*; D006023:Glycoproteins / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D007381:Intermediate Filament Proteins / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D014411:Neoplastic Stem Cells / Q000166:cytology* / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D064231:Nestin; D010455:Peptides / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055748:SOXB1 Transcription Factors / Q000378:metabolism; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D006023:Glycoproteins; D007381:Intermediate Filament Proteins; C491297:MSI1 protein, human; C577484:NES protein, human; D009419:Nerve Tissue Proteins; C577486:Nes protein, rat; D064231:Nestin; C000606023:PROM1 protein, human; D010455:Peptides; C000606025:Prom1 protein, rat; D016601:RNA-Binding Proteins; C527782:SOX2 protein, human; D055748:SOXB1 Transcription Factors