Tuesday 23 February 2010
Cancer Research UK funded scientists have discovered why some breast cancers are resistant to the commonly used drug tamoxifen, their findings are published in Cancer Research today (23 February).
Tamoxifen is given to most women for around five years after they are diagnosed with breast cancer to help prevent the disease from coming back. Some women gradually develop resistance to the treatment meaning their cancer is more likely to return. This discovery could lead to new drugs that counteract this resistance.
The team of scientists in the Breakthrough Breast Cancer Research Centre at The Institute of Cancer Research (ICR) found that when a gene called FGFR1 is turned on too much it causes resistance to tamoxifen and other hormone treatments.
When stimulated in this way breast cancer cells no longer rely on hormones to grow rapidly and spread, making hormone treatments like tamoxifen less effective.
Around a tenth of breast cancers have too much of the FGFR1 gene and these patients are more likely to see their cancer return after initial treatment and have a poor prognosis. But until now it wasn’t known whether FGFR1 was behind this poor prognosis. Understanding the role that FGFR1 plays could help personalise treatments for women.
In lab studies the scientists were able to switch off FGFR1, in cancer cells with too much of the gene, by adding a drug that blocks the function of FGFR1. Once FGFR1 was switched off hormone treatments were once more able to work and destroy the cancer cells. Understanding more about switching off FGFR1 could lead to new treatments that benefit patients who do not respond to tamoxifen.
Lead author Dr Nick Turner, a Cancer Research UK funded clinician scientist from the ICR, said: “We have known for some time that breast cancer patients with too much of the FGFR1 gene in their cancer are more likely to have a poor prognosis, but we did not know if FGFR1 was behind this. Understanding how this gene can cause tamoxifen resistance reveals a new drug target for treating breast cancers in patients who would otherwise have a poor outcome.
“There are a number of drugs in development that stop FGFR1 working, and clinical studies are investigating whether these drugs work against cancers with too many copies of this gene.“
“The next step is to set up a clinical trial to see whether a drug that blocks the action of this gene can counteract hormone therapy resistance in breast cancer patients. If these trials confirm our lab work we could be on the verge of a potentially exciting new treatment for breast cancer.”
Breast cancer is the most common cancer in the UK affecting more than 45,500 women each year.
Professor Alan Ashworth, Director of the Breakthrough Breast Cancer Research Centre at the ICR, said: "This new work provides another good example of how in the Breakthrough Centre we combine biological research with clinical application for patient benefit."
Dr Lesley Walker, director of cancer information at Cancer Research UK, said: “This research shows the importance of understanding how a patient’s response to treatment is defined by the genetic makeup of a tumour and how this changes over time. And it points the way to new treatment strategies targeted to this group of patients. Cracking the problem of resistance to treatments such as tamoxifen would be a major advance in treating breast cancer.”
- ENDS-
For media enquiries please contact Simon Shears in the Cancer Research UK press office on 020 7061 8054 or, out-of-hours, the duty press officer on 07050 264 059
Notes to Editors:
Turner, N., et al FGFR1 amplification drives endocrine therapy resistance and is a therapeutic target in breast cancerCancer Research (23 February 2010)
About The Institute of Cancer Research (ICR)
- The ICR is Europe’s leading cancer research centre.
- The ICR has been ranked the UK’s top academic research centre, based on the results of the Higher Education Funding Council’s Research Assessment Exercise.
- The ICR works closely with partner The Royal Marsden NHS Foundation Trust to ensure patients immediately benefit from new research. Together the two organisations form the largest comprehensive cancer centre in Europe.
- The ICR has charitable status and relies on voluntary income, spending 95 pence in every pound of total income directly on research.
- As a college of the University of London, the ICR also provides postgraduate higher education of international distinction.
- Over its 100-year history, the ICR’s achievements include identifying the potential link between smoking and lung cancer which was subsequently confirmed, discovering that DNA damage is the basic cause of cancer and isolating more cancer-related genes than any other organisation in the world.
- The ICR is home to the world’s leading academic drug development team. Several important anti-cancer drugs used worldwide were synthesised at the ICR and it has discovered an average of two preclinical candidates each year over the past five years.
For more information visit www.icr.ac.uk
About Breakthrough Breast Cancer
- Breakthrough Breast Cancer is a pioneering charity dedicated to the prevention, treatment and ultimate eradication of breast cancer. We fight on three fronts: research, campaigning and education.
- We fund ground-breaking research, campaign for better services and treatments and raise awareness of breast cancer. Through this work the charity believes passionately that breast cancer can be beaten and the fear of the disease removed for good.
Find more information at breakthrough.org.uk
About Cancer Research UK
- Cancer Research UK is the world’s leading charity dedicated to beating cancer through research.
- The charity’s groundbreaking work into the prevention, diagnosis and treatment of cancer has saved millions of lives. This work is funded entirely by the public.
- Cancer Research UK has been at the heart of the progress that has already seen survival rates double in the last thirty years.
- Cancer Research UK supports research into all aspects of cancer through the work of more than 4,500 scientists, doctors and nurses.
- Together with its partners and supporters, Cancer Research UK's vision is to beat cancer.
For further information about Cancer Research UK's work or to find out how to support the charity, please call 020 7121 6699 or visit www.cancerresearchuk.org