Inhibitors

An angiogenesis inhibitor is a substance that inhibits growth of new blood vessels. It can be endogenous or come from outside as drug or a dietary component.
Every solid tumor (in contrast to liquid tumors like leukemia) needs to generate blood vessels to keep it alive once it reaches a certain size. Usually, blood vessels are not built elsewhere in an adult body unless tissue repair is actively in process. The angiostatic agent endostatin and related chemicals can suppress the building of blood vessels, preventing the cancer from growing indefinitely. In tests with patients, the tumor became inactive and stayed that way even after the endostatin treatment was finished. The treatment has very few side effects but appears to have very limited selectivity.