Figure 4

Expression of VASH2 protein in tumors during the adenoma-carcinoma sequence. A, Normal intestinal tissue or intestinal polyps were examined for Vash2 expression by RT-PCR. Total RNA was isolated from normal intestinal tissue in C57BL/6 mice and Apc^Min/+ mice or from intestinal polyps in Apc^Min/+ mice. All samples were normalized to Gapdh and are expressed as relative ratios to wild-type (WT) controls. Note the increase in Vash2 levels in late-stage adenoma and adenocarcinoma in Apc^Min/+ mice. ^*P < 0.05, ^**P < 0.01, n = 3. B, H&E staining of late-stage adenoma in Apc^Min/+ mice and double-immunostaining of tomato lectin and VASH2 for detection of tumor vessels in the same region. Scale bar: 200 μm. C, A high magnification image of CD31 staining in adenocarcinoma, showing VASH2 expression around tumor vessels. Note that VASH2 expression was only found around these vessels in adenocarcinoma. Center inset, control staining with a nonspecific IgG. Right inset, higher magnification of tumor cells shown in D. Scale bar: 50 μm, 30 μm (right inset).