title: A small interfering RNA targeting vascular endothelial growth factor inhibits Ewing's sarcoma growth in a xenograft mouse model.
abstract: Angiogenesis plays an essential role in tumor growth and metastasis and is a promising therapeutic target for cancer. Vascular endothelial growth factor (VEGF) is a key regulator in vasculogenesis as well as in angiogenesis. TC71 human Ewing's sarcoma cells overexpress VEGF, with a shift in isoform production from membrane-bound VEGF189 to the more soluble VEGF165. Transfection of TC71 cells with a vector-based VEGF targeted small interfering RNA expression system (VEGFsi) inhibited VEGF165 expression by 80% and VEGF165 protein production by 98%, with no alteration in VEGF189 expression. Human microvascular endothelial cell proliferation and migration induced by conditioned medium from VEGFsi-transfected TC71 cells was significantly less than that induced by conditioned medium from TC71 cells and control vector-transfected TC71 cells. Furthermore, after s.c. injection into athymic nu/nu mice, the tumor growth of VEGFsi-expressing TC71 cells was significantly less than that of parental or control vector-transfected cells. Vessel density as assessed by CD31 immunohistochemical analysis and VEGF165 expression as assessed by Northern blotting were also decreased. Intratumor gene therapy with polyethylenimine/VEGFsi also resulted in tumor growth suppression. When inoculated into the tibias of nude mice, VEGFsi-expressing TC71 cells induced osteolytic bone lesions that were less severe than those induced by control groups. These data suggest that targeting VEGF165 may provide a therapeutic option for Ewing's sarcoma.
authors.affiliation: Division of Pediatrics and Departments of Cancer Biology and Surgical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Guan
authors.forename: Zhichao
authors.initials: Z
authors.lastname: Zhou
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.forename: Shu-Fang
authors.initials: SF
authors.lastname: Jia
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Liu
authors.forename: Eugenie S
authors.initials: ES
authors.lastname: Kleinerman
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000378:metabolism; D017209:Apoptosis; D015153:Blotting, Western; D002460:Cell Line; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D004250:DNA Topoisomerases, Type II / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D010957:Plasmids / Q000235:genetics; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000032:analysis; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D012512:Sarcoma, Ewing / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D015996:Survival Rate; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics* / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays / Q000379:methods*
chemical_list: D000951:Antigens, Neoplasm; D004250:DNA Topoisomerases, Type II; D004268:DNA-Binding Proteins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D018719:Erb-b2 Receptor Tyrosine Kinases; D042461:Vascular Endothelial Growth Factor A