Bone marrow-derived endothelial cells contributed to colitis-associated colon cancer angiogenesis.

<p>(A) Blood vessels were stained with 647 WGA (blue), which was injected retrorbitally. Confocal microscopy analysis from living tissue specimens showed that the BM-derived cells (green) infiltrated the stroma, and a portion of cells were hemmed by a WGA-647-positive (blue) margin at the tumor endothelium. Double-positive cells were observed lining the vessels. (B) The frozen tumors sections were stained with an anti-CD31 antibody to detect BM-derived endothelial cells (green). GFP-positive cells (green) with CD31-positive margins were seen in the tumor endothelium. C (CMT93) and D (CT26) xenograft tumor tissues isolated from BM transplantation mice were stained with anti-CD31 (red) antibodies. GFP-positive cells were observed around the tumor vessels, and some lined the endothelium.</p