Sie können Bookmarks mittels Listen verwalten, loggen Sie sich dafür bitte in Ihr SLUB Benutzerkonto ein.
Medientyp:
E-Artikel
Titel:
Minor Contribution of Bone Marrow‐Derived Endothelial Progenitors to the Vascularization of Murine Gliomas
Beteiligte:
Machein, Márcia Regina;
Renninger, Sabine;
De Lima‐Hahn, Elisete;
Plate, Karl H.
Erschienen:
Wiley, 2003
Erschienen in:
Brain Pathology, 13 (2003) 4, Seite 582-597
Sprache:
Englisch
DOI:
10.1111/j.1750-3639.2003.tb00487.x
ISSN:
1750-3639;
1015-6305
Entstehung:
Anmerkungen:
Beschreibung:
Until recently, it was generally accepted that the vascularization of solid tumors occurred exclusively through the sprouting and co‐option from preexisting blood vessels. Growing evidence now suggests that bone marrow‐derived endothelial progenitor cells (EP) circulate in the blood and may play an important role in the formation of new blood vessels in certain tumors. Whether endothelial progenitors participate in the vascularization of brain tumors has not yet been evaluated. In this study, we examined the contribution of EP to tumor angiogenesis in a murine glioma tumor model. Donor bone marrow cells obtained from transgenic mice constitutively expressing β‐galactosidase or GFP either ubiquitously or transcriptionally regulated by an endothelial specific promotor Tie‐2 were injected into lethally irradiated adult mice. After bone marrow reconstitution by donor cells, mice were implanted with syngeneic GL261 murine glioma cells. Morphological and confocal 3‐dimensional analysis showed that the majority of the engrafted donor marrow cells were expressing hematopoietic and/or microglia markers, but did not appreciably contribute to the tumor vasculature. Implantation of glioma cells genetically engineered to overexpress VEGF produced highly vascularized tumors. However, the number of endothelial progenitors incorporated in the tumor vasculature did not increase. These data strongly suggest that neovascularization in the brain might fundamentally be regulated by the sprouting of pre‐existing vessels and implicate that circulating endothelial progenitors do not play a significant role in this process.