'Broccoli pill' could prevent cancer

Scientists say there could one day be a "broccoli pill" that protects women against breast cancer.

Researchers from the University of Illinois at Chicago have designed a chemical compound based on a naturally occurring anticancer agent found in the vegetable.

Tests in animals have shown promising results.

If tests in humans confirm their findings, the researchers say the compound could be developed into a once-a-day pill or vitamin for cancer prevention.

It could be available in as little as seven years, they say.

At the moment, only tamoxifen is available as a breast cancer-prevention drug for high-risk women, but the researchers say it can only protect against oestrogen-dependent tumours, whereas the "broccoli pill" could protect against all forms.

UK science experts welcomed the study, but said cancer prevention therapy was a good idea, but very difficult in practice.

Toxic

The team presented their research to the American Chemical Society meeting in Boston.

The synthetic compound they have developed is called oxomate.

It is based on a naturally occurring cancer-preventative agent called sulforaphane which is found in vegetables including cabbage and Brussels sprouts, as well as broccoli.

Both the synthetic and natural versions boost the amount of phase II enzymes in the body, which can detoxify cancer-causing chemicals.

"There is a question mark as to what degree healthy people should be exposed to a hefty dose of a specific compound"

Dr Richard Sullivan, Cancer Research UK

But sulforaphane itself can be toxic in high doses, the researchers warn.

In laboratory tests, it killed animal cells. It is also difficult and expensive to reproduce for medications.

The Chicago researchers made the synthetic version less toxic by removing the chemicals which appear to be responsible.

When they compared the two versions by applying them to liver cells in laboratory tests oxomate was seven times less toxic than sulforaphane.

It is also cheaper and easier to make, the researchers say.

In tests on rats, those that were fed oxomate after being exposed to cancer-causing chemicals had a 50% reduction in breast cancer tumours compared to rats who were not given the compound.

'Definite benefit'

Lead researcher Jerry Kosmeder, research assistant professor at the University of Illinois, said a dose of the cancer-preventing chemical from a pill could be better than from the vegetables themselves, because the dose could be controlled.