Fig. 3

The expression and localization of VEGF by immunohistochemistry staining. a: control; b: endostatin; c: radiotherapy; d: radiotherapy with endostatin treatment. e: Comparison of the percentages of cells in each group that stained positive for VEGF. VEGF was localized mainly in the cytoplasm and was positively expressed in all four groups. The expression of VEGF was at a particularly high level in the radiotherapy group compared with that in other three groups. The rates of positive VEGF expression in each group were as follows: control group, 30.12% ± 0.63%; endostatin group, 6.12% ± 0.18%; radiotherapy group, 40.05% ± 1.27%; and radiotherapy with endostatin treatment group, 12.30% ± 0.25%. The intensity at which VEGF stained in the endostatin and radiotherapy with endostatin treatment groups was lower than the intensity at which it stained in the control group. In addition, the endostatin group displayed lighter VEGF staining than the other three groups (n = 8 per group, **P < 0.01) (200×)