Figure 3. Increased leukocyte-vessel wall interactions and ICAM-1 expression in tumor vessels in vivo by zebularine and TSA.

Adhering (A) and rolling (B) leukocytes in flank tumor vessels of C57Bl6 mice bearing B16F10 mouse melanoma tumors. Mice were treated with zebularine (n=5) or TSA (n=5). Data are presented as medians with interquartile ranges. Statistical significance was assessed in comparison to values in tumor vessels of untreated mice (n=5; control) (*p<0.01, **p<0.001). (C) Typical intravital fluorescence microscopy images of an untreated, zebularine treated and TSA treated tumor vessel. Leukocytes are fluorescently labelled with Rhodamine 6G. Vessels are indicated by the dashed lines, examples of leukocytes by the arrow heads. The bar represents 25 mm. Because the stills have rather low resolution, the video recordings can be observed at ‘http://www.fdg.unimaas.nl/AngiogenesisLab/mirrorsite/movies.htm’. For numbers of mice and vessels see Table 1. Expression levels of ICAM-1, VCAM-1 and E-selectin in B16F10 (D) and LS174T (E) tumor tissues of mice treated with zebularine or TSA measured by quantitative real-time RT-PCR. Results are plotted as mean values (± SEM) of relative mRNA expression compared to untreated control mice (*p<0.05, **p<0.001 vs. control mice).