Galectin-3 as an immunohistochemical tool to distinguish pilocytic astrocytomas from diffuse astrocytomas, and glioblastomas from anaplastic oligodendrogliomas.
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.
Neder
Luciano
L
Department of Pathology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
Marie
Suely K Nagahashi
SK
Carlotti
Carlos Gilberto
CG
Gabbai
Alberto Alain
AA
Rosemberg
Sérgio
S
Malheiros
Suzana M F
SM
Siqueira
Rodrigo Proto
RP
Oba-Shinjo
Sueli Mieko
SM
Uno
Miyuki
M
Aguiar
Paulo Henrique
PH
Miura
Flavio
F
Chammas
Roger
R
Colli
Benedicto Oscar
BO
Silva
Wilson Araujo
WA
Zago
Marco A
MA
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
D037502:Galectin 3; D012333:RNA, Messenger