Breakthrough research holds the promise of breast cancer treatment
Scientists have re-written the rule book on breast cancer by using the genetic fingerprint of a tumour to create 10 completely new subtypes of the disease. This new approach could mean a dramatic change in the way drugs are tailored to treat women with the condition.
This work is the largest ever global gene study of breast cancer tissue. It involved analysing the DNA and RNA (this translates DNA into proteins) of 2,000 tumour samples taken from women diagnosed with breast cancer between five and 10 years ago.
The research discovered a number of completely new breast cancer genes, which means that new types of drugs could be created specifically to target them. It has also uncovered the relationship between the genes and known cell signalling pathways (networks that control cell growth and division). This knowledge could help scientists discover how these gene faults cause cancer.
“Our results will pave the way for doctors in the future to diagnose the type of breast cancer a woman has, the types of drugs that will work, and those that won’t, in a much more precise way than is currently possible, “ said study co-lead author, Professor Carlos Caldas, senior group leader at Cancer Research UK’s Cambridge Research Institute and the Department of Oncology, University of Cambridge.
“This research won’t affect women diagnosed with breast cancer today. But in the future, breast cancer patients will receive treatment targeted to the genetic fingerprint of their tumour. Essentially we’ve moved from knowing what a breast tumour looks like under a microscope to pinpointing its molecular anatomy – and eventually we’ll know which drugs it will respond to.
“The next stage is to discover how tumours in each subgroup behave – for example do they grow or spread quickly? And we need to carry out more research in the laboratory and in patients to confirm the most effective treatment plan for each of the 10 types of breast cancer.”
“We know that survival rates for breast cancer have really gone up tremendously over the last 25 years,” said Dr Sofia Danovi, senior science communications officer at Cancer Research UK. “Patients have benefited from treatments that have their origins 20 to 30 years ago, so these things do take time. I think it’s important to point out that the women who gave their consent to have their tumours analysed for this study were aware that it wouldn’t affect them. They decided to take part because they knew that it would benefit their daughters and granddaughters.
“This study really has the potential to revolutionise the way we approach breast cancer, both in the clinic and in the laboratory. The new breast cancer genes can give us all sorts of information. They can offer insights into the biology of the tumour, so they may help doctors predict whether a tumour will respond to a particular treatment, whether the tumour is likely to spread, and whether it’s likely to return after treatment.”
“The detail that this study has given us is unlike anything else we’ve ever seen in breast cancer. It’s like the difference between looking at a planet with the naked eye and looking at it with a telescope.
“It might also help doctors identify women who don’t need to be treated aggressively, and that’s really important. It would mean saving women with breast cancer from treatment that isn’t going to work, and from treatment they don’t need to have.”
A quick look at the latest statistics shows the size of the problem, just in the UK, where breast cancer is the most common cancer. A woman’s lifetime risk of being diagnosed with breast cancer is one in eight. In 2008 nearly 47,700 women found out that they had breast cancer. (The figure for men in that year was about 340.)
Advances in treatment have already made a huge difference to survival rates: in the 1970s five out of 10 women survived breast cancer for more than five years and that figure has now risen to eight out of 10. Improvements of the kind predicted as a result of this study should mean that in the future doctors will be able to give far more accurate survival rates. And it could be a huge step forward in the drive for individual treatment for each patient.
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Cancer Research UK - www.cancerresearchuk.org