Expression of galectin-1 mRNA correlates with the malignant potential of human gliomas and expression of antisense galectin-1 inhibits the growth of 9 glioma cells.
Although its precise function has not yet been established, galectin-1 seems to play a role in tumor progression. In this study, we investigated galectin-1 mRNA expression in human glioma specimens and glioma cell lines. Northern blot analysis showed higher galectin-1 mRNA levels in glioma tissues. The 0.7-kb galectin-1 mRNA transcript was detected, and the expression level correlated with the malignant state, from low-grade astrocytoma to glioblastoma. In several human glioma specimens, immunohistochemical examination with antiserum against a synthetic peptide corresponding to the predicted C-terminal sequence of the protein showed high levels of galectin-1 expression. To clarify the correlation between the expression of galectin-1 and the malignancy of gliomas, we examined whether expression of antisense galectin-1 would suppress tumor growth in rat 9L cells that express high levels of galectin-1. The cells were transfected with a plasmid DNA that produces antisense galectin-1 mRNA under the control of the metallothionein promoter, and stable clones expressing low levels of galectin-1 protein in comparison with control clones were isolated. Cells with low levels of galectin-1 displayed dramatic phenotypic changes in their morphology and growth properties compared with vector-transfected control 9L cells. Our data suggest that decreased expression of galectin-1 may arrest the growth of rat 9L cells.
Yamaoka
K
K
Department of Biochemical Cell Research, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan. yamaoka@rinshoken.or.jp
Mishima
K
K
Nagashima
Y
Y
Asai
A
A
Sanai
Y
Y
Kirino
T
T
D015152:Blotting, Northern; D001932:Brain Neoplasms / Q000235:genetics* / Q000628:therapy; D002455:Cell Division / Q000235:genetics; D048429:Cell Size / Q000235:genetics; D037483:Galectin 1; D015972:Gene Expression Regulation, Neoplastic; D005910:Glioma / Q000235:genetics* / Q000628:therapy; D006388:Hemagglutinins / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D016372:RNA, Antisense; D012333:RNA, Messenger / Q000032:analysis; D014162:Transfection; D014407:Tumor Cells, Cultured
D037483:Galectin 1; D006388:Hemagglutinins; D016372:RNA, Antisense; D012333:RNA, Messenger