Potent doses of broccoli sprout extract activate a “detoxification” gene and may help prevent cancer recurrence in survivors of head and neck cancer, according to a trial by the University of Pittsburgh Cancer Institute, confirming preliminary results presented last year at the American Association for Cancer Research Annual Meeting.
“With head and neck cancer, we often clear patients of cancer only to see it come back with deadly consequences a few years later,” said lead author Julie Bauman. “Unfortunately, previous efforts to develop a preventative drug to reduce this risk have been inefficient, intolerable in patients and expensive. That led us to ‘green chemoprevention’–the cost-effective development of treatments based upon whole plants or their extracts.”
Cruciferous vegetables, such as broccoli, cabbage and garden cress, have a high concentration of the naturally occurring molecular compound sulforaphane, which previously has been shown to protect people against environmental carcinogens.
Dr. Bauman and her colleagues treated human head and neck cancer cells in the laboratory with varying doses of sulforaphane and a control, and compared them to normal, healthy cells that line the throat and mouth. The sulforaphane induced both types of cells to increase their levels of a protein that turns on genes that promote detoxification of carcinogens, like those found in cigarettes, and protect cells from cancer.
In a small preclinical trial, 10 healthy volunteers drank or swished fruit juice mixed with broccoli sprout extract for several days. The volunteers had no significant problems tolerating the extract and the lining of their mouths showed that the same protective genetic pathway activated in the laboratory cell tests was activated in their mouths, meaning that the sulforaphane was absorbed and directed to at-risk tissue.