Bone marrow-derived endothelial cells contribute to angiogenesis in murine WEHI and JC tumors.

The goal of this study was to determine the contribution of bone marrow-derived circulating endothelial progenitor cells to the formation of endothelial cell linings of tumor vessel walls. The proportion of male endothelial cells in female JC and WEHI tumors was measured in male BALB/c mice and in female mice displaying complete marrow chimerism, after receiving male bone marrow cells. The gender origin of the perivascular endothelial cells was determined by fluorescent in situ hybridization (FISH) analysis of adjacent cuts of the tumors, using CD31 and Y-chromosomes as markers. High proportions of male cells were detected in the perivascular endothelial cell linings of the JC (60 +/- 4%) and WEHI (67 +/- 4%) tumors after implantation into normal male mice. Furthermore, in marrow chimeric female mice, very high levels of male cells were observed in the endothelilal cell linings of the tumor vessel walls of both tumor types, after bone marrow transplantation. We conclude that JC and WEHI tumors can serve as a murine experimental model and that bone marrow cells from these can be manipulated and cultured in vitro for use in studies of tumor vessel walls after transplantation into myeloablated recipients.