title: Galectin-3 as an immunohistochemical tool to distinguish pilocytic astrocytomas from diffuse astrocytomas, and glioblastomas from anaplastic oligodendrogliomas.
abstract: The distinction of astrocytomas and oligodendrogliomas, mainly pilocytic astrocytomas (PILOs) from infiltrating astrocytomas and oligodendrogliomas (ODs), and high-grade oligodendrogliomas from glioblastomas (GBMs), poses a serious clinical problem. There is no useful immunohistochemical (IHC) marker to differentiate these gliomas, and sometimes the differential diagnosis between them is arbitrary. We identified galectin-3 (Gal-3) as a possible tool to differentiate them based on gene expression profiles of GBMs. We confirmed the differential expression in 45 surgical samples (thirteen GBMs; seven PILOs; 5 grade II ODs; 5 anaplastic oligodendrogliomas [AODs], including 2 Oligo-astrocytomas; 8 diffuse astrocytomas [ASTs], and 7 non-neoplastic samples) by quantification of Gal-3 gene expression by real-time quantitative PCR (rt-PCR). Higher expression of Gal-3 was observed in GBMs and PILOs than in OD, AODs and ASTs. The IHC expression of Gal-3 was evaluated in 90 specimens (fifteen PlLOs, fourteen ASTs, 10 anaplastic astrocytomas, fifteen GBMs, eleven ODs, fifteen AODs, and 10 dysembryoplastic neuroepithelial tumors). The mean labeling score for Gal-3 determined according to the percentage of labeled cells in the tumor bulk was significantly different in GBMs versus AODs and in PILOs versus ASTs. Hence, Gal-3 is differentially expressed in central nervous system tumors, making IHC detection of Gal-3 a useful tool in distinguishing between these gliomas.
authors.affiliation: Department of Pathology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
authors.forename: Luciano
authors.initials: L
authors.lastname: Neder
authors.forename: Suely K Nagahashi
authors.initials: SK
authors.lastname: Marie
authors.forename: Carlos Gilberto
authors.initials: CG
authors.lastname: Carlotti
authors.forename: Alberto Alain
authors.initials: AA
authors.lastname: Gabbai
authors.forename: Sérgio
authors.initials: S
authors.lastname: Rosemberg
authors.forename: Suzana M F
authors.initials: SM
authors.lastname: Malheiros
authors.forename: Rodrigo Proto
authors.initials: RP
authors.lastname: Siqueira
authors.forename: Sueli Mieko
authors.initials: SM
authors.lastname: Oba-Shinjo
authors.forename: Miyuki
authors.initials: M
authors.lastname: Uno
authors.forename: Paulo Henrique
authors.initials: PH
authors.lastname: Aguiar
authors.forename: Flavio
authors.initials: F
authors.lastname: Miura
authors.forename: Roger
authors.initials: R
authors.lastname: Chammas
authors.forename: Benedicto Oscar
authors.initials: BO
authors.lastname: Colli
authors.forename: Wilson Araujo
authors.initials: WA
authors.lastname: Silva
authors.forename: Marco A
authors.initials: MA
authors.lastname: Zago
mesh_terms: D000293:Adolescent; D000328:Adult; D001254:Astrocytoma / Q000175:diagnosis* / Q000378:metabolism; D001932:Brain Neoplasms / Q000175:diagnosis / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D005260:Female; D037502:Galectin 3 / Q000235:genetics / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics / Q000502:physiology; D005909:Glioblastoma / Q000175:diagnosis* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D009837:Oligodendroglioma / Q000175:diagnosis* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013194:Staining and Labeling / Q000379:methods
chemical_list: D037502:Galectin 3; D012333:RNA, Messenger