We quantified gene and protein expression of members of the vascular endothelial growth factor (VEGF) and angiopoietin systems and studied localization of VEGF, its receptors VEGFR-1 and VEGFR-2, Angiopoietin (Ang)-1 and Ang-2, and their receptor, in HCC in noncirrhotic and cirrhotic livers.
Ang-2 levels in the hepatic vein significantly correlated with Ang-2 mRNA expression in HCC, but Ang-2 levels in the peripheral vein did not correlate.
We investigated immunohistochemical expression of vascular endothelial growth factor (VEGF), angiopoietins (Ang-1 and Ang-2), hypoxia-induced factor-1alpha (HIF-1alpha) and thrombospondin-1 (TSP-1) in 60 specimens of surgically resected HCC.
Ang-2 and VEGF mRNAs in HCC were significantly higher than those in NCL tissue (P < 0.05), whereas the Ang-1 and Tie2 mRNAs showed no statistical significance (P > 0.05), though slightly lower level of Ang-1 mRNA in HCC was observed.
Furthermore, a high Ang-2/1 mRNA ratio in HCC was closely associated with tumor portal vein invasion, tumor diameter, and the microvessel density level as assessed by CD34 immunostaining.
The aim of this study was to determine the expression and cellular localization of VEGF, Ang1, and Ang2 in specimens of resected human HCC using in situ hybridization and immunohistochemical staining and to examine their relationship to microvessel density (MVD) and tumor size.