title: Modeling astrocytoma pathogenesis in vitro and in vivo using cortical astrocytes or neural stem cells from conditional, genetically engineered mice.
abstract: Current astrocytoma models are limited in their ability to define the roles of oncogenic mutations in specific brain cell types during disease pathogenesis and their utility for preclinical drug development. In order to design a better model system for these applications, phenotypically wild-type cortical astrocytes and neural stem cells (NSC) from conditional, genetically engineered mice (GEM) that harbor various combinations of floxed oncogenic alleles were harvested and grown in culture. Genetic recombination was induced in vitro using adenoviral Cre-mediated recombination, resulting in expression of mutated oncogenes and deletion of tumor suppressor genes. The phenotypic consequences of these mutations were defined by measuring proliferation, transformation, and drug response in vitro. Orthotopic allograft models, whereby transformed cells are stereotactically injected into the brains of immune-competent, syngeneic littermates, were developed to define the role of oncogenic mutations and cell type on tumorigenesis in vivo. Unlike most established human glioblastoma cell line xenografts, injection of transformed GEM-derived cortical astrocytes into the brains of immune-competent littermates produced astrocytomas, including the most aggressive subtype, glioblastoma, that recapitulated the histopathological hallmarks of human astrocytomas, including diffuse invasion of normal brain parenchyma. Bioluminescence imaging of orthotopic allografts from transformed astrocytes engineered to express luciferase was utilized to monitor in vivo tumor growth over time. Thus, astrocytoma models using astrocytes and NSC harvested from GEM with conditional oncogenic alleles provide an integrated system to study the genetics and cell biology of astrocytoma pathogenesis in vitro and in vivo and may be useful in preclinical drug development for these devastating diseases.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine.
authors.forename: Robert S
authors.initials: RS
authors.lastname: McNeill
authors.affiliation: Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine.
authors.forename: Ralf S
authors.initials: RS
authors.lastname: Schmid
authors.affiliation: Division of Neuropathology, Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine.
authors.forename: Ryan E
authors.initials: RE
authors.lastname: Bash
authors.affiliation: Curriculum in Genetics and Molecular Biology, University of North Carolina School of Medicine.
authors.forename: Mark
authors.initials: M
authors.lastname: Vitucci
authors.affiliation: Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine.
authors.forename: Kristen K
authors.initials: KK
authors.lastname: White
authors.affiliation: Division of Neuropathology, Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Werneke
authors.affiliation: Biological and Biomedical Sciences Program, University of North Carolina School of Medicine.
authors.forename: Brian H
authors.initials: BH
authors.lastname: Constance
authors.affiliation: Department of Radiation Oncology, Emory University School of Medicine.
authors.forename: Byron
authors.initials: B
authors.lastname: Huff
authors.affiliation: Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine; Division of Neuropathology, Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine; Department of Neurology, Neurosciences Center, University of North Carolina School of Medicine; rmiller@med.unc.edu.
authors.forename: C Ryan
authors.initials: CR
authors.lastname: Miller
mesh_terms: D000483:Alleles; D000818:Animals; D001253:Astrocytes / Q000473:pathology*; D001254:Astrocytoma / Q000209:etiology* / Q000235:genetics / Q000473:pathology; D002461:Cell Line, Transformed; D005818:Genetic Engineering; D005909:Glioblastoma / Q000209:etiology / Q000235:genetics / Q000473:pathology; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D058953:Neural Stem Cells / Q000473:pathology*; D009857:Oncogenes