Comparative Study of the Nestin Expression in the Invasive Border of Glioblastoma and in Reactive Glial Tissue
MA Idoate, R Diez Valle, J Echeveste, MD Lozano, T Labiano, A Panizo. University of Navarra, Pamplona, Navarra, Spain
Background: We have previously shown that surgery done with 5-ala fluorescence allows highly precise separate sampling of the invasive border of the tumor in glioblastoma (GBM). Nestin is a type VI intermediate filament considered as a marker for tumor stem cell and could be used in the identification of peripheral glioblastoma cells. However, an ample characterisation of this marker in different pathological contexts is not available. To study the value of nestin, invasive cells in the periphery of glioblastoma were compared with the reactive glia in both active and chronic gliosis.
Design: In 32 consecutive patients the fluorescent quality of the tissue was used to take biopsies from the tumor center, from the border and from the surrounding normal-looking tissue. This group was compared with the reactive glia in 30 biopsies from patients with brain metastasis, vascular malformations and mesial temporal gliosis in chronic epilepsy. All samples were analysed by immunostaining against nestin and GFAP.
Results: In all GBM cases, central tumor areas and pathological vessels stained strongly with nestin. The density of nestin expression decreased gradually around the tumor, but in all cases strong nestin expression was also seen in the vessels walls and in many different cells in the peritumor areas. Some of these cells looked like typical astrocytes while many others had one or two wide processes or no process at all. In metastases and vascular malformations active gliosis around also showed intense expression of nestin with cell phenotype similar to the GBM border. However, in mesial (chronic) gliosis, nestin expression in the glia was absolutely negative. Glia GFAP expression was similar in the periphery of GBM and in the other series.
Conclusions: Nestin is a glial acute reaction marker, not a specific tumor stem cell marker, as strong nestin expression accompanies glioblastoma as well as acute glial reaction. However, in the chronic mature glia, no expression of nestin is observed at all.
Tuesday, March 23, 2010 1:00 PM
Poster Session IV # 228, Tuesday Afternoon