Investigating Endothelial Precursor Cells (EPCs)

Recent studies suggest that cells in the bone marrow-endothelial precursor cells (EPCs)-can provide a blood supply to cancerous tumors. The purpose of this study is to collect brain tumor and blood samples to look for these EPCs in the samples and analyze the growth signals that may help blood vessels to grow in tumors. Researchers will study the following in the samples: 1) the number of blood vessels in the tumor; 2) the levels of growth factors in the tumor and blood; 3) the levels of circulating EPCs in the blood; and 4) the changes in the genes and proteins in the blood and tumor that influence growth factor levels. Participants will be 18 years of age or older and have evidence of a brain tumor that requires surgery. From this surgery they will donate blood and tumor samples. Participants will have follow-up visits 4 to 8 weeks after surgery, then at 3-month intervals for two-and-one-half years, then at 6-month intervals thereafter. At these visits, participants will undergo a physical exam, a brain scan, and blood work.