The purpose of this study is to assess the safety of rhEndostatin, to determine how much of the drug stays in the patients blood (pharmacokinetics), to assess the development of proteins in the blood that are produced by the body (antibodies)using rhEndostatin, to determine the effect of rhEndostatin on the formation of new blood vessel factors, and to perform an analysis of the effect of rhEndostatin on circulating endothelial precursor cells (cells in the body that help the tumor build more blood vessels).