The VM Mouse Model of Glioblastoma Multiforme

Information is presented on the new VM-M3 mouse model for glioblastoma multiforme (GBM). The VM-M3 tumor arose in the brain of inbred VM strain, which is known to have a high incidence of spontaneous brain tumors. The failure to develop effective treatments for GBM has been due in part to the failure of animal models to manifest the key invasive properties of the disease. Scherer originally described the properties of malignant brain tumors in terms of their invasive behavior independent of cell classification. These properties are referred to as Secondary Structures and involve growth and invasion along blood vessels, through ventricles, white matter tracts, through the corpus callosum and across pial membranes. While extracranial metastasis is not often reported, numerous reports show that GBM can be highly metastatic if the cells gain access to extracranial sites. The VM-M3 GBM model is unique in displaying the Secondary Structures of Scherer and showing systemic metastasis when grown outside the CNS. The VM-M3 cells express the luciferase gene and can be used to assess quantitatively distal CNS invasion. Evidence is presented showing the calorie restriction reduces VM-M3 CNS invasion. The VM-M3 model will be useful for evaluating new therapies for GBM.