Monoclonal antibody to stage-specific fetal brain 68-kDa glycoprotein (FGP68) revealed increased FGP68 expression in human primary brain tumors.
We have produced a novel rat IgG(2a) monoclonal antibody against a stage-specific fetal brain glycoprotein of 68 kDa (FGP68), and succeeded in applying it to staining paraffin sections. To gain some insight into the pathobiological significance of this FGP68, this monoclonal antibody was used in immunohistochemical studies to compare the expression of FGP68 and Ki-67 antigen (MIB-1) in 235 primary brain tumors. Approximately half of the glioblastomas multiforme (GBMs) (44/75) and anaplastic astrocytomas (9/17) as well as some astrocytomas (5/30), medulloblastomas (2/14) and primitive neuroectodermal tumors (2/10) had tumor cells that expressed FGP68; however, pilocytic astrocytomas (0/7), oligodendrogliomas (0/15), ependymomas (0/6), schwannomas (0/21), meningiomas (0/22) and pituitary adenomas (0/18) did not express FGP68. The values of the MIB-1 labeling index were statistically higher in GBMs (0.005< P<0.01, Wilcoxon rank-sum test) and anaplastic astrocytomas (0.025< P<0.05) that expressed FGP68 than in those that did not. Normal brain tissue from 20 individuals aged 3-75 years was negative for FGP68 and MIB-1. We conclude that primary brain tumors express FGP68, one of the oncofetal proteins derived from fetal brain, and that FGP68 expression in certain brain tumor cells may depend, in part, on proliferation potential. Based on the possibility that the stage-specific FGP68 plays an important role in brain embryogenesis, some of FGP68-expressing tumor cells might phylogenetically revert to more primitive cells.
Kato
Shinsuke
S
Department of Neuropathology, Institute of Neurological Sciences, Faculty of Medicine, Tottori University, Nishi-cho 36-1, Yonago 683-8504, Japan. kato@grape.med.tottori-u.ac.jp
Shinozawa
Takao
T
Nagashige
Hiroaki
H
Nakamura
Miyuki
M
Asano
Yoshiya
Y
Takikawa
Miki
M
Kato
Masako
M
Awaya
Akira
A
Hirano
Asao
A
Ohama
Eisaku
E
D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D015153:Blotting, Western; D001921:Brain / Q000196:embryology* / Q000473:pathology; D001923:Brain Chemistry; D001932:Brain Neoplasms / Q000737:chemistry* / Q000473:pathology; D005260:Female; D006023:Glycoproteins / Q000032:analysis* / Q000276:immunology*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008875:Middle Aged; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D012189:Retrospective Studies
D000911:Antibodies, Monoclonal; D006023:Glycoproteins; D019394:Ki-67 Antigen