Rb2 and p27kipl cooperate to control mobilization of angiogenic progenitors from the bone marrow. Proc Natl Acad Sci USA

Department of Molecular Biology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 06/2005; 102(19):6890-5. DOI: 10.1073/pnas.0405823102
Source: PubMed


Neoangiogenesis involves both bone marrow-derived myelomonocytic and endothelial progenitor cells as well as endothelial cells coopted from surrounding vessels. Cytokines induce these cells to proliferate, migrate, and exit the cell cycle to establish the vasculature; however, which cell cycle regulators play a role in these processes is largely unknown. Here, we report that mice lacking the cell cycle inhibitors p130 and p27 show defects in tumor neoangiogenesis, both in xenografts and spontaneously arising tumors. This defect is associated with impaired mobilization of endothelial and myelomonocytic angiogenic progenitors from the bone marrow. This article documents the role of these molecules in angiogenesis and further suggests that cell expansion and mobilization from the bone marrow of angiogenic precursors are separable events.

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