Angiopoietin 2 expression is related to histological grade,vascular density, metastases, and outcome in prostate cancer

BACKGROUND. In several malignant tissues, the angiopoietins are principal regulators of vascular growth and regression, but in normal prostate and prostate tumors the role of the angiopoietins is unknown. METHODS. Angiopoietin (ang) 1 and 2 were immunolocalized in TUR-diagnosed prostate tumors with long follow-up and the expression was related to vascular density and clinopathological variables. RESULTS. Ang 1 was strongly expressed in the basal epithelial cell layer in non-malignant tissue, whereas tumors had lower levels localized to the epithelial cells. A weak ang 2 immunoreaction was observed in non-malignant tissue and in low to intermediate Gleason score (GS) tumors, with a similar expression pattern. However, most high GS tumors showed an intense ang 2 staining. Ang 2 was significantly correlated to GS, density of endoglin stained blood vessels, metastases, and to cancer specific survival. CONCLUSIONS. We conclude that ang 2 probably is an important regulator of angiogenesis in prostate cancer. Prostate 62: 394-399, 2005. (C) 2004 Wiley-Liss, Inc.