Scientists are beginning to understand why thousands of women become resistant to a leading breast cancer drug.
The discovery could lead to the development of new treatments with the potential to save millions of lives.
Until now, experts did not know why up to half of breast cancer sufferers develop a resistance to tamoxifen.
Breast cancer affects more than 45,000 women in Britain every year. Although the drug is suitable for only three quarters of breast cancer cases it is considered one of the most effective on the market.
Study leader Dr Rebecca Riggins, from Georgetown University in Washington, found that resistant cancer cells contained fewer numbers of the target “receptors” the drug is designed to attack.
The findings, published in the journal Cancer Research, mean that scientists can work on changing the drug to attack alternative targets. They may also help to identify more quickly those patients for whom tamoxifen is no longer working.
Dr Rebecca Riggins said: “The magnitude of this health issue is huge. It is clear that we need to understand why this resistance occurs.”
Copyright PA Business 2008