Expression of endothelial nitric oxide synthase and vascular endothelial growth factor in association with neovascularization in human primary astrocytoma.
OBJECTIVE
To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma.


METHODS
Thirty-seven primary astrocytomas and 4 astrocytic hyperplasia samples were collected and divided into three groups according to histological grade. The expression of eNOS, VEGF and factor VIII related antigen (FVIIIRAg) were assayed by immunohistochemistry. Microvascular density was assessed by FVIIIRAg immunoreactivity. The intensity of immunoreactivity was graded according to the percentage of positive tumor cells.


RESULTS
No eNOS and VEGF were expressed in the astrocytes and vascular endothelium in astrocytic hyperplasia. The expression of eNOS or VEGF was light in low-grade astrocytoma and strong in glioblastoma. eNOS expression in astrocytoma was very positively correlated with VEGF. eNOS and VEGF expression in anaplastic astrocytoma was median in contrast to the low grade astrocytoma and glioblastoma. Lower microvascular density was found in low grade astrocytoma than that in higher grade malignant ones. The expressions of eNOS and VEGF were correlated with microvascular density and tumor malignancy.


CONCLUSIONS
This finding suggests that eNOS and VEGF may have cooperative effect in tumor angiogenesis and play an important role in the pathogenesis of primary astrocytoma.
Pan
Jian-Wei
JW
Department of Neurosurgery, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China. swordman_pan@hotmail.com
Zhan
Ren-ya
RY
Tong
Ying
Y
Zhou
Yong-qing
YQ
Zhang
Ming
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000098:blood supply* / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000378:metabolism* / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
D014408:Biomarkers, Tumor; D042461:Vascular Endothelial Growth Factor A