Mesothelioma: Angiogenesis Therapies

Cancer cells, like other cells in the human body, rely for their growth on a rich supply of blood. They must be surrounded by an effective network of capillaries and larger blood vessels that nourish the cells. The medical term for the process of developing this network is angiogenesis.
In fact, fast-growing cancers are highly efficient at promoting angiogenesis. They produce angiogenesis promoters that create capillaries and a network of blood vessels around the tumor. The tumor is nourished with an increasing supply of oxygen-rich blood, and it grows and spreads (or metastasizes).

Understanding that angiogenesis is fundamental to the process of how tumors grow and metastasize, medical researchers started to investigate how they could slow down, stop, or reduce angiogenesis. If they could do this, they reckoned, they could starve the tumor to death - or at least slow its growth significantly. The National Cancer Institute has created an illustrated teaching tool to better understand how angiogenesis works.

A number of antiangiogenesis drugs, also called angiogenesis inhibitors or angiogenic inhibitors, have been developed. When administered to laboratory animals with tumors, they have caused the tumors to shrink or even disappear. Endostatin, combrestatin, angiostatin, thrombospondin, and vascular endothelial growth inhibitor (VEGI) are among these experimental drugs.

A few of these drugs are now being tested on humans. One of them, combrestatin, destroys the lining of blood vessels around tumors. Another, endostatin, acts by impeding the growth of new blood vessels around the tumors. For endostatin there have recently been some promising developments. Harvard's Dana-Farber Cancer Institute released an updated report on Phase 1 trials of the angiogenic inhibitor and says it exhibits virtually no toxicity even at high doses, while shrinking tumors in two of 28 advanced cancer patients and slowing disease progression in four others for more than six months.

This area of cancer research holds promise for the treatment of mesothelioma tumors, but it is very much in the early and experimental stages.