Expression and clinical significance of EGFL7 in malignant glioma.

Purpose: Tumor angiogenesis is an important factor for the continuous growth of human malignancies and can be used to predict the prognosis for patients. In the current study, we examined the expression of EGF-like domain 7 (EGFL7), an endothelial cell-derived secreted factor, in malignant gliomas and explored its clinical significance. Methods: We determined the steady-state mRNA levels of EGFL7 from 36 fresh glioma samples by semi-quantitative RT-PCR and the protein levels from 45 paraffin-embedded glioma samples by immunohistochemistry, respectively. Normal brain tissues from 10 patients with brain trauma were used as control. We also analyzed the correlations between the expression levels of EGFL7 and various clinical parameters, including patient gender, age, tumor grade, tumor proliferation marker Ki-67, and microvessel density (MVD). Results: We found that EGFL7 was not detectable in normal brain tissues, but was up-regulated in both tumor cells and vascular endothelial cells within malignant glioma. The expression level of EGFL7 in malignant glioma significantly correlated with the tumor grade, Ki-67 expression and MVD ( P < 0.01). Conclusions: Our data suggest that EGFL7 expression is a novel predictive factor for the clinical progression of malignant glioma, and may constitute a therapeutic target for anti-angiogenesis therapy in patients with the disease. [ABSTRACT FROM AUTHOR]