A component of broccoli could help combat breast cancer, scientsts say
The vegetable, already hailed as a so-called "superfood", contains a chemical capable of targeting the cells which fuel the growth of tumours.
A component of broccoli called sulforaphane targets and kills cancer stem cells as well as preventing new tumours from growing, according to researchers at the University of Michigan.
Current chemotherapies do not work against cancer stem cells. Researchers believe that eliminating the cancer stem cells is key to controlling cancer.
The study, published in the journal Clinical Cancer Research, charts how scientists at the university's Comprehensive Cancer Centre tested the effects of sulforaphane in experiments involving mice and cell cultures.
Prof Duxin Sun, the author of the study, said: "Sulforaphane has been studied previously for its effects on cancer, but this study shows that its benefit is in inhibiting the breast cancer stem cells.
"This new insight suggests the potential of sulforaphane or broccoli extract to prevent or treat cancer by targeting the critical cancer stem cells."
Researchers took mice with breast cancer and injected varying concentrations of sulforaphane from the broccoli extract.
They then used several established methods to assess the number of cancer stem cells in the tumours.
These measures showed a marked decrease in the cancer stem cell population after treatment with sulforaphane, with little effect on the normal cells.
Cancer cells from mice treated with sulforaphane were also unable to generate new tumours.
The researchers then tested sulforaphane on human breast cancer cell cultures in the lab, finding similar decreases in the cancer stem cells.
Researchers are currently developing a method to extract and preserve sulforaphane.
The tests involved higher concentrations of sulforaphane than are available by simply eating broccoli.