Indena builds evidence on safety of soy extract for post-menopausal women

Consuming a standardized soy extract does not stimulate the growth of breast cancer tumours as suspected by some scientists, and may in fact reduce tumour progression, suggests new research from Indena.

Like other suppliers of soy ingredients, Italian plant extracts firm Indena is targetting women looking for an alternative to hormone replacement therapy to regulate menopausal symptoms.

However although animal studies suggest that prepubertal consumption of soy may protect against breast cancer in later life, concerns have been raised by scientists that point to soy's oestrogen-like effects and its potential impact on raising risk of breast cancer.

"All products reported to have an oestrogen-like effect are suspected of increasing the proliferation of some cells due to the fact that this effect is mediated by the receptor also involved in breast cancer," explained Paolo Morazzoni, Indena's scientific director.

"This is why ostrogen therapy after menopause has been linked to increased risk of breast cancer," he added.

Concerns that plant oestrogens may also have the same effect as HRT have already damaged Novogen's sales, a company producing red clover for the menopause market.

The problem is compounded by the fact that women looking for remedies for menopause symptoms are also at higher risk of breast cancer because of their age, and a small percentage of these may have or have experienced the disease, added Morazzoni.

In a bid to counter the controversy raised by some scientific reports in recent times, Indena asked researchers in Rome to investigate consumption of its Soyselect in an experimental animal model (xenograft MCF-7) for post-menopausal women with breast cancer.

Speaking at a symposium on the Role of Soy in Preventing and Treating Chronic Disease in Chicago last month, scientists from the Policlinico Gemelli Hospital said results of their tests provide evidence that the standardized soy extract, which contains isoflavones and saponins, does not stimulate the growth of breast cancer tumours.

Daniela Gallo explained that "soy-derived products may induce a moderate oestrogenic effect on oestrogen-dependent cells, without increasing cellular proliferation and tumour growth".

The study also highlighted a decrease in the expression of other genes involved in tumour progression and angiogenesis, such as Thrombospondin 1 and Transforming Growth Factor â2.

These experimental results have yet to be confirmed by a full clinical analysis but could show a "collateral positive effect on breast cancer risk reduction", said Morazzoni.