Revista de citología e histología

Combined Expression of Nestin and SPARC Identifies In Situ Tumor Cells in Astrocytic Tumors of all Grades

Abstract

Kifah Aljammal, Marie-Françoise Ritz, Archana Ramadoss, Guido Sauter, Jean-Louis Boulay and Luigi Mariani

Background: Malignant gliomas are heterogeneous, diffuse and invasive by nature. Histopathological identification of glioma tumor cells is mandatory to characterize the tumors and the extent of infiltration in the surrounding normal parenchyma.
Methods: In order to identify specific markers for tumor cells not expressed in non-neoplastic brain tissues, we used a well-annotated tissue microarray (TMA) containing 45 samples from patients that suffered from several subtypes of low grade and high grade gliomas (pilocytic astrocytoma, oligoastrocytoma, low grade astrocytoma, anaplastic astrocytoma, primary and secondary glioblastomas), non-glial tumors (medulloblastoma and metastasis) as well as fetal, epileptic, and gliotic specimens used as non-tumoral control tissues. The TMA was assessed for 24 proteins involved in tumor proliferation, migration, invasion, and differentiation, or acting as transcription factors and metabolic enzymes.
Results: This immunohistological analysis revealed that nestin and secreted protein, acidic and rich in cysteine (SPARC) are expressed in tumor cells in all glioma subtypes and developmental tissues but rarely in mature epileptic tissue. In addition to these two markers, the expression of mutated isocitrate dehydrogenase 1 (IDH1(R132H)) also identified tumor cells but only in some subtypes of gliomas.
Conclusions: Taken together, our data suggest that the combination of nestin and SPARC expression characterizes tumor glioma cells. These proteins may represent relevant glioma immunohistological markers that might be molecular targets in glioma therapy.