Figure 4.

Quantitative analyses on the morphological changes in the tumour microvessels. (a) The length of abluminal circumference of the vessels analysed in this study was smaller than 40 µm, and there was no significant difference between the groups. (b) The percentage of mural cell coverage of endothelial cells was significantly lower in the vascular endothelial growth factor (VEGF)-transfected tumours than the control tumours. (c) The frequency of abluminal processes on endothelial cells per µm was significantly higher in the VEGF-transfected tumours than the control tumours. (d) The difference in the frequency of luminal processes was not significant. *P < 0.0001.