Most of them are stored in the extracellular matrix in a bioactive form. Also, receptors for angiogenesis factors have been demonstrated on the endothelial cell surface and the signal transduction mechanisms responsible for the induction of the angiogenic phenotype are currently being investigated. Quantitation of microvessel density in tumor specimens has been perfomed. The evaluation of blood vessel density in a tumor may help to predict the risk of metastases or recurrence. Recent observations have confirmed this hypothesis for different types of tumors, including breast cancer.
Cancer results from an abnormal, rapid growth of cells.
These cells divide and multiply unchecked, often becoming tumors that invade healthy tissue. They also quickly adapt to changes in their environment and are capable of developing mechanisms of resistance to accepted treatment regimes. For these reasons, the focus of much current research is on new approaches to the disease and agents that work along new biological pathways. Cancer is a serious disease. Every minute there is another death from cancer in the United States.