Immunohistochemical characterization of spontaneous and acrylonitrile-induced brain tumors in the rat.

Abstract

Twenty-eight spontaneously occurring glial tumors (previously diagnosed as astrocytomas, oligodendrogliomas, and gliomas) and eleven granular cell tumors (GCTs) were selected for evaluation using a panel of immunohistochemistry (IHC) stains (Ricinus communis agglutinin type 1 [RCA-1], ionized calcium-binding adapter molecule 1 [Iba-1], OX-6/major immunohistocompatibility complex class II, oligodendrocytes transcription factor 2 [Olig2], glial fibrillary acidic protein [GFAP], S100 beta, glutamine synthetase, neurofilament, proliferating cell nuclear antigen). In addition, nine brain tumors from a 2-year drinking water study for acrylonitrile were obtained from the Acrylonitrile Group, Inc. Based on IHC staining characteristics, Olig2+ oligodendrogliomas were the most commonly diagnosed spontaneous tumor in these animals. Many of the spontaneous tumors previously diagnosed as astrocytomas were RCA-1+, Iba-1+ and negative for GFAP, S100beta, and glutamine synthetase; the diagnosis of malignant microglial tumor is proposed for these neoplasms. Three mixed tumors were identified with Olig2+ (oligodendrocytes) and Iba-1+ (macrophage/microglia) cell populations. The term mixed glioma is not recommended for these tumors, as it is generally used to refer to oligoastrocytomas, which were not observed in this study. GCT were positive for RCA-1 and Iba-1. All acrylonitrile tumors were identified as malignant microglial tumors. These results may indicate that oligodendrogliomas are more common as spontaneous tumors, while acrylonitrile-induced neoplasms are microglial/histiocytic in origin. No astrocytomas (GFAP, S100 beta, and/or glutamine synthetase-positive neoplasms) were observed.

• Authors: Holly Meredith Kolenda-Roberts, Nancy Harris, Emily Singletary, Jerry F Hardisty
• Journal: Toxicologic pathology (Toxicol Pathol) Vol. 41 Issue 1 Pg. 98-108 (Jan 2013) ISSN: 1533-1601 [Electronic] United States
• PMID: 22821367 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Basic Helix-Loop-Helix Transcription Factors
• Biomarkers, Tumor
• Glial Fibrillary Acidic Protein
• Nerve Tissue Proteins
• Olig2 protein, rat
• Oligodendrocyte Transcription Factor 2
• Acrylonitrile

Topics

• Acrylonitrile (toxicity)
• Animals
• Basic Helix-Loop-Helix Transcription Factors (chemistry, metabolism)
• Biomarkers, Tumor (chemistry, metabolism)
• Brain (drug effects, pathology)
• Brain Chemistry
• Brain Neoplasms (chemically induced, chemistry, metabolism, pathology)
• Disease Models, Animal
• Glial Fibrillary Acidic Protein (chemistry, metabolism)
• Immunohistochemistry
• Nerve Tissue Proteins (chemistry, metabolism)
• Oligodendrocyte Transcription Factor 2
• Rats