Scientist investigating mutation link to breast cancer drug resistance

A leading scientist is investigating how oestrogen receptor (ER) mutations can cause drug resistance in secondary breast cancer patients receiving anti-hormone treatments such as tamoxifen. The Breast Cancer Campaign-funded research could lead to treatments for breast cancers that have become resistant to commonly-used anti-hormone drugs.

Up to 80% of breast cancers are 'oestrogen receptor (ER)-positive', which means they overproduce the ER protein and their growth is driven by the hormone oestrogen. People with ER-positive breast cancer receive anti-hormone therapies such as tamoxifen, which block the effects of oestrogen. However, some breast cancers can develop resistance to these treatments, meaning they can spread to other parts of the body - becoming incurable.

Previous research has found that 25% of metastatic breast cancers present with mutations in the oestrogen receptor (ER) gene, which provides the instructions to make the ER protein.

Professor Simak Ali, based at Imperial College London, has been awarded around £200,000 funding from research charity Breast Cancer Campaign to investigate the role of these oestrogen receptor mutations in breast cancers that have become resistant to anti-hormone treatments, and find new ways to stop this resistance from developing.

To study these ER gene mutations more closely, Professor Ali will introduce these mutations into breast cancer cells in the lab, and test these cells for their response to oestrogen and anti-hormone drugs. The cells will then be implanted into mice, to study how quickly they are able to grow and spread.

Finally, Professor Ali will test whether blocking a protein called CDK7, which works with ER to drive the growth of ER-positive breast cancer, could reverse resistance to anti-hormone treatments.

Katherine Woods, Senior Research Communications Manager at Breast Cancer Campaign, said:

"Professor Ali's research will help us uncover the role of oestrogen receptor mutations in anti-hormone drug resistance, which could lead to new treatments that improve the chances of survival for thousands of people."