[Morphological changes in osteosarcoma xenografts in nude mice after inhibiting angiogenesis by Ad-VEGF-siRNA].
OBJECTIVE
Vascular endothelial growth factor (VEGF) is a critical stimulator for angiogenesis of osteosarcoma. This study was to investigate the morphological changes in osteosarcoma xenografts in nude mice after inhibiting angiogenesis by Ad-VEGF-siRNA.


METHODS
The animal model of osteosarcoma xenografts was constructed by subcutaneous inoculation of osteosarcoma MG63 cells into nude mice. The mice were randomly divided into three groups, 15 mice in each group: group A and control groups B and C. The tumor nodules were injected with Ad-VEGF-siRNA in group A, an equal dose of Ad-EGFP and PBS, respectively, in groups B and C. The volume and weight of tumors were measured every two days after injection and the growth curves were drawn. The tumor samples were observed and analyzed using HE staining. Angiogenesis was assessed by immunohistochemical staining using anti-VEGF and CD31 antibodies. The ultrastructure of vasculogenic mimicry (VM) was observed using transmission electron microscopy (TEM).


RESULTS
The mean volume, weight, microvessel density (MVD) and VEGF expression of tumors in Ad-VEGF-siRNA-treated group were significantly lower than those in the control groups. MVD was positively correlated to VEGF expression, with a correlation coefficient of 0.9989. The number of VM was 1.40+/-0.55 in the Ad-VEGF-siRNA group, which was significantly less than those in the two control groups.


CONCLUSIONS
Ad-VEGF-siRNA could effectively block angiogenesis in osteosarcoma xenografts in nude mice.
Wang
Jia-Qi
JQ
Department of Orthopedics, Tongji Hospital, Tongji University, Shanghai 200065, P. R. China.
Gao
You-Shui
YS
Mei
Jiong
J
Xue
Hua-Ming
HM
Wang
Shu-Qing
SQ
Cai
Xuan-Song
XS
D000818:Animals; D001859:Bone Neoplasms / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D045744:Cell Line, Tumor; D005260:Female; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D055806:Microvessels / Q000473:pathology / Q000648:ultrastructure; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000517:prevention & control*; D012516:Osteosarcoma / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D011897:Random Allocation; D047368:Tumor Burden; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism* / Q000502:physiology
D034741:RNA, Small Interfering; D042461:Vascular Endothelial Growth Factor A