Elastase is an enzyme that shortens a cellular chemical, cyclin E, that is involved in controlling the cell cycle. The shortened version of cyclin E accelerates the cell cycle, making cancer cells proliferate faster. Firestone showed that I3C prevents the elastase shortening of cyclin E, thereby arresting development of breast cancer cells.
For more than 15 years, Firestone, Bjeldanes and their colleagues have studied the anti-cancer benefits of vegetables in the cabbage family that are lumped together in the genus Brassica and, because of their cross-shaped flowers, are often referred to as cruciferous vegetables.
Though the anti-cancer benefits have been recognized since the 1970s, the mechanism is only now being discovered, in part through the work of Firestone, Bjeldanes and their UC Berkeley colleagues.
"We have connected the dots on one extremely important pathway" by which indole-3-carbinol works, Firestone said.
In previous work, they found that indole-3-carbinol interferes with more than cell proliferation. It also disrupts the migration and alters adhesion properties of cancer cells, as well as counteracts the survival ability of cancer cells, all of which are implicated in cancer cell growth. To have such broad downstream effects, I3C must act at the beginning of a major cellular pathway, Firestone said. The newly reported research pins this activity to elastase and its effect on cyclin E.
Bjeldanes noted that I3C is available as a supplement and is a preferred preventative treatment for recurrent respiratory papillomatosis, a condition involving non-malignant tumors of the larynx. Improved versions of the chemical could thus help treat cancers other than those of the breast and prostate.
Graduate student Ida Aronchik and recent Ph.D. recipient Hanh H. Nguyen, along with colleagues in the Firestone and Bjeldanes labs, have already chemically modified I3C and boosted its act
|Contact: Robert Sanders|
University of California - Berkeley