Angiogenesis is the formation of new blood vessels from existing vessels. Angiogenesis continues the growth of the vasculature by processes of sprouting and splitting. This process of angiogenesis is  been controlled by chemical signals in the body. Angiogenic factors produced by tumoral cells bind to endothelial cell receptors and initiate the sequence of angiogenesis. Angiogenesis is a key player in the growth of cancer cells and metastasis of tumors, it can be considered both an attractive target and major factor in progression of cancer. Basically, it is the formation of new capillary vasculature out of preexisting blood vessels under the regulation of growth factors and inhibitors. A balance between pro-angiogenic and antiangiogenic growth factors and cytokines tightly controls angiogenesis.