A recombinant humanized monoclonal antibody directed against the vascular endothelial growth factor (VEGF), a pro-angiogenic cytokine. Bevacizumab binds to VEGF and inhibits VEGF receptor binding, thereby preventing the growth and maintenance of tumor blood vessels. OR A substance found in various nuts, beans, seeds, fruits, and vegetables. It may also be used in dietary supplements. Beta-sitosterol may help lower cholesterol levels in the blood by decreasing the amount of cholesterol absorbed from the diet. It may also slow the growth of some types of cancer cells and kill them. It is a type of phytosterol.