The rTSR1 suppressed angiogenesis and cell proliferation but induced apoptosis in tumors. Tumor paraffin sections were probed for microvessel density, tumor cell proliferation, and apoptosis through immunofluorescence staining, using (A) anti-endomucin, (B) TUNEL staining, and (C) anti-PCNA (Proliferating cell nuclear antigen) respectively. The corresponding quantification of the staining is presented in the bar graph on the right. The percentage of proliferating cells/field is the ratio of the nuclear PCNA-positive cells to the total number of nuclei in the field. Scale bar: 200 μm. Corresponding quantifications are presented in the bar graph on the right. Data represent the mean ± SD of four fields per section, four sections per tumor, and two tumors per group. Statistical analysis was performed by Student’s t test. ** p < 0.01.