Immunohistochemical analysis of tumor vessels in ApcMin/+ and ApcMin/+/ Vash2-/- mice. A, Double staining for CD31 and LYVE1 in intestinal polyps from ApcMin/+ mice and ApcMin/+/Vash2-/- mice at 16 weeks of age. Scale bar: 100 μm. n = 3. B, Double staining for CD31 and Desmin of tumor vessels in intestinal polyps from ApcMin/+ mice and ApcMin/+/Vash2-/- mice. Note the pericytes were detached from endothelia in ApcMin/+ mice, whereas they returned to cover vessel walls in ApcMin/+/Vash2-/- mice. Scale bar: 10 μm, n = 3. C, Semi-thin section stained with toluidine blue and CD31. Pericyte coverage of normal tumor vessels was found in tumors of ApcMin/+/Vash2-/- mice. Asterisks, endothelial cells. Arrowheads, pericytes. Scale bars: 10 μm, n = 3. D, Ratio of pericyte coverage. Open columns represent ApcMin/+ mice and closed columns represent ApcMin/+/Vash2-/- mice. Pericytes per blood vessel was estimated by counting semi-thin section in 3 separate fields of tumor lesions in ApcMin/+ mice and ApcMin/+/Vash2-/- mice at a magnification of × 1000. **P < 0.01, n = 3.