Active ingredients of soya may help beat breast cancer

Researchers are investigating whether it is possible to turn the active ingredients of soya into a useful medicine that may help to beat breast cancer, the British Pharmaceutical Conference heard today.

Soya contains isoflavones, which are thought to have potential therapeutic benefit in breast cancer and other conditions, including osteoporosis. Epidemiological studies indicate that women in the Far East, who have high dietary intake of soya products, have lower rates of breast cancer than Western women.

Dr Karen James and colleagues from the School of Pharmacy and Biomedical Sciences at the University of Portsmouth, have been investigating ways of converting natural isoflavones into a therapeutic agent. Dr James explained: “There are few drugs based on isoflavones available for clinical use and there are good reasons for this. Isoflavones are not very potent and they are rapidly metabolised in the body. While lifetime intake of low doses in the diet might be beneficial, developing a drug therapy requires a new approach.”

The Portsmouth work is aimed at finding a way to make the isoflavone compound stay longer in the body whilst retaining, or enhancing, the beneficial biological properties. The researchers used derivatives of daidzien, a known isoflavone. They tested the effect of the compounds on the growth of hormone dependent breast cancer cells and found they had a stimulant effect at lower concentrations and a reduction in cancer cell growth at high concentrations.

These studies are now underway and the researchers are also hoping to synthesise new, more potent derivatives. Dr James described the results to date as encouraging, but cautioned that it is early days. “Isoflavones are present in many foods and they tend not to produce toxic effects, but we do not know yet whether there might be side effects from a more potent synthetic compound.” She added: “The natural compounds have a number of actions — as well as binding to oestrogen receptors, they can act as antioxidants and as enzyme inhibitors. It seems beneficial to look at any natural product that has such a diverse range of properties and to try to insert those properties into useful drugs.”

The Royal Pharmaceutical Society of Great Britain (RPSGB) is the regulatory and professional body for pharmacists in England, Scotland and Wales. The primary objective of the RPSGB is to lead, regulate and develop the pharmacy profession.