To stop cancer, use your bean?

A compound found in beans, nuts, and wheat bran shows potent antitumor activity both in vitro and in vivo. This finding presents the possibility that a diet high in these foods may help prevent cancer; likewise, it may form the basis of new treatments for established tumors.

Angiogenesis—the formation of new blood vessels—involves the migration and proliferation of endothelial cells to form tubular structures able to carry blood. Angiogenesis is an important part of normal development and wound healing. It is also critical for the growth of tumors, creating an avenue for tumor cells to acquire oxygen and nutrients; indeed, without its own blood supply a tumor cannot grow much larger than the size of a pea.

Because of its involvement in a key angiogenesis pathway, the enzyme phosphoinositide 3-kinase (PI3K) is a desirable target for anticancer therapies. However, variables such as toxicity and insolubility have hindered the search for a safe and effective inhibitor.

Now, in the 15 September issue of Cancer Research, Marco Falasca of University College London's Sackler Institute (London, UK) and his colleagues report that inositol pentakisphosphate (Ins(1,3,4,5,6)P₅), a naturally occurring, water-soluble compound, specifically inhibited the activity of the enzyme. Falasca's team found that Ins(1,3,4,5,6)P₅ inhibited PI3K activity in cultured endothelial cells, reduced endothelial cell migration in vitro, and blocked angiogenesis in mice. In mice with human ovarian cancer xenografts, the compound also reduced tumor growth as much as does cisplatin, a drug commonly used in treatment of ovarian cancers.

Unlike conventional chemotherapeutic agents, Ins(1,3,4,5,6)P₅ did not seem to cause toxic side effects. As Falasca tells Lab Animal, “The possible use of nontoxic, natural compounds to target cancer cells is attractive. Furthermore, the observation that inositol polyphosphates are easily absorbed by oral administration makes [the compound] even more promising in terms of therapeutic potential.”

In addition, because the chemical is found naturally in legumes and other foods, it seems reasonable that including these in your diet may help ward off the development of cancer.

Falasca's group thinks that Ins(1,3,4,5,6)P₅ holds great promise as an anticancer treatment—either on its own or in combination with other drugs. They are currently gathering additional data in preparation for clinical trials.