title: Antisense-mediated reduction in thrombospondin-1 expression reduces cell motility in malignant glioma cells.
abstract: Thrombospondin-1 (TSP-1) is a multifunctional matrix protein implicated in cancer cell adhesion, migration, invasion, inhibition of angiogenesis and activation of latent transforming growth factor-beta. The involvement of TSP-1 in the motility of malignant glioma cells was investigated by transfection of TSP-1 complementary deoxyribonucleic acid (cDNA) sense and antisense expression vectors into the glioblastoma cell line T98G-G7 that secretes high amounts of TSP-1. TSP-1 production in the 3 antisense cDNA-transfected clones was significantly reduced to 51%, 43% and 47% compared to the host T98G-G7 cells. Motility of the 3 clones was evaluated by invasion assay and compared to the motility of host T98G-G7 cells and 2 sense-transfected clones. Migration of cells was significantly reduced in the 3 antisense-transfected clones with reduced TSP-1 production to 56%, 61% and 43% compared to the host T98G-G7 cells. The host T98G-G7 and another TSP-1-secreting A172 and YMG5 glioblastoma cells were also treated with a synthetic peptide, WSHWSPWSSCSVTCG, which includes 3 consecutive sequences of the adhesion sites in the TSP-1 molecule and with a control peptide. The synthetic peptide significantly inhibited the migration of T98G-G7 and A172 cells in a dose-related manner. Maximum inhibition of migration was achieved by 100 microg/ml of the peptide and the reduction of cell motility compared to untreated cells was 34.6 % and 53.9 %, respectively. On the other hand, the inhibition of migration by the peptide was minimal in YMG5 cells, which secretes a smaller amount of TSP-1 than T98G-G7 and A172 cells. These results suggest that TSP-1 secreted by malignant glioma cells is involved in the motility of glioma cells.
authors.affiliation: Department of Neurosurgery, Yamanashi Medical University, Tamaho-machi, Yamanashi, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Amagasaki
authors.forename: A
authors.initials: A
authors.lastname: Sasaki
authors.forename: G
authors.initials: G
authors.lastname: Kato
authors.forename: S
authors.initials: S
authors.lastname: Maeda
authors.forename: H
authors.initials: H
authors.lastname: Nukui
authors.forename: H
authors.initials: H
authors.lastname: Naganuma
mesh_terms: D015153:Blotting, Western; D002448:Cell Adhesion; D002465:Cell Movement; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005822:Genetic Vectors; D005910:Glioma / Q000378:metabolism*; D006801:Humans; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D010455:Peptides / Q000494:pharmacology; D011485:Protein Binding; D019700:Thrombospondin 1 / Q000096:biosynthesis*; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D018076:DNA, Complementary; D016376:Oligonucleotides, Antisense; D010455:Peptides; D019700:Thrombospondin 1