Figure 7. Physapubescin decreases the protein expression of vimentin in 786-O cells and inhibits in vivo angiogenesis in 786-O xenograft tumors.

(A) The protein expression of vimentin at indicated treatments for 24 hours was analyzed by Western blotting. GAPDH was detected as a loading control. A representative blot was shown from three independent experiments. The protein levels were quantified by densitometry. Density ratios relative to GAPDH were shown on the top of each Western blotting band. (B) Immunostaining of CD31 protein in 786-O xenograft tumors. The mice bearing 786-O tumors were randomly divided, pair-matched into treatment and control groups of six mice each, and five days on and two days off dosing was begun with vehicle control or physapubescin at 30 mg/kg. At the end of the experiment; tumors were excised from each mouse, fixed in buffered formalin, embedded in paraffin blocks and tissue slides were prepared. Control immunostaining was performed with IgG isotype alone; Slides were counterstained with hematoxylin and photographed using a light microscope. Original magnification: X200. (C) CD31-positive cells were counted in 12 fields in each group. The percentage of CD31-positive cells was calculated as vessel density and presented as mean ± SEM. The mean vessel density is significantly lower in the physapubescin treatment group (n = 6) than that in the vehicle control group (n = 6). “*” and “**” denote “P < 0.05” and “P < 0.01” respectively.