Suppression of glioblastoma cell growth following antisense oligonucleotide-mediated inhibition of fibroblast growth factor receptor expression.
Astrocytes exhibit significant changes in fibroblast growth factor receptor (FGFR) gene expression during malignant progression. These changes include induction of FGFR1 and concomitant loss of FGFR2 expression. The induction of FGFR1 is believed to endow malignant astrocytes with a selective growth advantage. Glioblastoma (the most malignant form of astrocytoma) cell lines, which exhibit the same pattern of FGFR gene expression as glioblastoma biopsies, were used to evaluate the contribution of FGFR1 expression to glioblastoma cell growth. Addition of phosphorothioate-modified antisense oligonucleotides complementary to the initiation site or the alpha exon of the FGFR1 gene suppressed growth of human glioblastoma-derived cell lines. Reverse antisense controls or antisense oligonucleotide complementary to FGFR2 had no effect on proliferation. Consistent with its growth-suppressive effect, FGFR1 antisense oligonucleotides markedly reduced expression of both FGFR1 mRNA and high-affinity bFGF binding sites, whereas FGFR1 reverse antisense control oligonucleotide had no effect. Antisense oligonucleotide targeted to the alpha exon of the FGFR1 gene suppressed alpha and beta alternatively spliced FGFR1 mRNA isoforms but did not alter the expression of related FGFR family members. Fluorescein-labeled antisense and reverse control oligonucleotides demonstrated cellular uptake and nuclear accumulation. These results indicate that alterations in FGFR expression may contribute to malignant proliferation in human astrocytomas. These findings also illustrate the high degree of selectivity that can be obtained with antisense oligonucleotides, a property that is essential for employing these reagents therapeutically.
Yamada
S M
SM
Department of Neurosurgery, Nippon Medical School, Tokyo, Japan.
Yamaguchi
F
F
Brown
R
R
Berger
M S
MS
Morrison
R S
RS
D015139:Blotting, Southern; D001932:Brain Neoplasms / Q000473:pathology*; D002452:Cell Count / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D003864:Depression, Chemical; D016222:Fibroblast Growth Factor 2 / Q000737:chemistry / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000096:biosynthesis* / Q000235:genetics; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D005909:Glioblastoma / Q000473:pathology*; D006801:Humans; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis* / Q000235:genetics; D051496:Receptor, Fibroblast Growth Factor, Type 1; D017468:Receptors, Fibroblast Growth Factor / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D005456:Fluorescent Dyes; D016376:Oligonucleotides, Antisense; D017468:Receptors, Fibroblast Growth Factor; D016222:Fibroblast Growth Factor 2; D005346:Fibroblast Growth Factors; C496348:FGFR1 protein, human; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D016650:Fluorescein-5-isothiocyanate