Trial Information

Circulating Endothelial Progenitor Cells in Gliomas

Angiogenesis, or the development of new blood vessels, appears to be one of the keys to
tumor survival. Areas of new blood vessel growth, or neovascularization, such as with
trauma or tissue ischemia, appear to release factors that stimulate production of
endothelial cells from progenitor stem cells located in the bone marrow. Endothelial cells
for the inside lining of blood vessels are important in the formation of viable and
functional blood vessel conduits. Recent work suggests that tumors-including primary brain
tumors-secrete many of the same stimulatory growth factors as normally incite endothelial
cells to be produced and turned out into the circulation. Initial evidence suggests that
these circulating endothelial progenitor cells (EPCs) play a role in the impressive
neovascularization seen with tumors. In this study, we wish to investigate the interaction
of gliomas and EPCs to elucidate a potential role for EPCs in tumor formation, response to
therapy, progression, and overall survival, as well, to identify potential new targets for
anti-tumor and/or anti-angiogenic therapies using genomic and proteomic techniques.

Patients suspected of having, or with prior biopsy proof of, a WHO grade II-IV central
nervous system (CNS) glial tumor(s) seen in the Surgical Neurology Branch, NINDS, will be
considered for entry into this study. Tissue samples of tumor resected as part of standard
care will be collected at surgery and preserved for research. Blood samples will also be
collected. Blood will also be collected from anonymous normal volunteers who donate blood
at the NIH Blood Bank; these anonymous donors will serve as controls.