Selenium added to broccoli compound combats melanoma

In an article published in the March, 2009 issue of the journal Clinical Cancer Research, researchers at Pennsylvania State University College of Medicine report their finding of a potent effect of a compound consisting of selenium and isothiocyanates from cruciferous vegetables such as broccoli against the potentially deadly cancer known as melanoma.

Previous research conducted by Penn State associate professor of pharmacology, pathology and dermatology Gavin Robertson and his colleagues found that isothiocyanates target a protein known as Akt3 which is increased in approximately 70 percent of tumors. Recognizing that the known cancer fighting ability of isothiocyanates would require the administration of impractical amounts of the compounds, the team replaced isothiocyanantes’ sulfur bonds with selenium to create new compounds called isoselenocyanates. "Selenium deficiency is common in cancer patients, including those diagnosed with metastatic melanoma," explained Robertson. "Besides, selenium is known to destabilize Akt proteins in prostate cancer cells."

When mice injected with melanoma cells were treated with isothiocyanates or isoselenocyanates, animals that received the selenium-containing compound had approximately 60 percent less tumor development compared with those that received isothiocyanates. In additional experiments with human melanoma cell lines, tumor growth was decreased by 30 to 70 percent. "We found that the selenium-enhanced compounds significantly reduced the production of Akt3 protein and shut down its signaling network," Dr Robertson stated.

"There are currently no drugs to target the proteins that trigger melanoma," Dr Robertson noted. "We have developed drugs from naturally occurring compounds that can inhibit the growth of tumors in mice by 50 to 60 percent with a very low dose."

"We have harnessed something found in nature to target melanoma," he remarked. "And since we only need tiny amounts to kill the cancer cells, it means even less toxic side-effects for the patient."

—D Dye

March 02, 2009