We can think of cancer cells as over-worked engines, ferociously churning through fuel at a rate faster than they were designed for. The fuel feeding these engines isn’t always the same.
Our series of blogs exploring the achievements of Breast Cancer Campaign and Breakthrough Breast Cancer continues with a look at the pioneering research we have been funding into triple negative breast cancer. The previous post highlighted our Male Breast Cancer Study and the achievements so far helping to improve our understanding of the disease in men.
We can think of cancer cells as over-worked engines, ferociously churning through fuel at a rate faster than they were designed for. The fuel feeding these engines isn’t always the same. In the same way car engines may run on petrol or diesel, different types of breast cancer are driven by different fuels. Cells of the two most common sub-types of breast cancer, oestrogen receptor (ER) positive and HER2 positive, rely on stimulation by different molecules to power their unrestrained division and growth.
This reliance on a particular type of fuel has also given us a helping hand in designing effective, targeted treatments. Drugs like tamoxifen, aromatase inhibitors and Herceptin all damage the fuel supply for these cancer cells and have revolutionised treatment for these patients. But there is a sub-type of breast cancer that makes up around 15% of all breast cancer cases which we still haven’t worked out how to target. This group of breast cancers, called triple negative breast cancer, lack (as far as we know) any discernable features that could be hit with a drug like tamoxifen or Herceptin. (You can find out more about this type of the disease in our Redefining Triple Negative Breast Cancer blog).
In 2007, aware of the pressing need to improve treatments for patients with triple negative breast cancer, we set up a research unit at Guy’s Hospital and King’s College London – right in the heart of the hospital’s breast clinic. This research programme, led by Professor Andrew Tutt, aims to get under the surface of the genetic and molecular characteristics of triple negative breast cancer so that it can be more accurately diagnosed and treated. As we’ve said before – it’s time to stop seeing this form of the disease for what it isn’t and start seeing what makes individual patients stand out from the crowd.
Professor Tutt is an eminent oncologist and cancer researcher whose expertise in triple negative breast cancer and clinical trials are leading to fantastic advances in our understanding of this aggressive form of the disease. Ultimately, these will form the basis of new ways to diagnose it and lead to the development of the much needed targeted treatments.
Let’s take a look at some of the key breakthroughs that his team have made.
It’s a micro world after all
Tiny biological molecules exist, similar in structure to DNA, which can interfere with the activity of genes. They are called microRNA and they play an essential role in the controlled regulation of genes. It’s known that changes in the level of specific microRNAs are linked to cancer and the team at King’s College London have found several that are associated with triple negative breast cancer.
Importantly, they have also shown that these microRNAs influence cellular functions that could explain the aggressive nature of the disease. The microRNAs associated with triple negative breast cancer could become useful biomarkers to help improve diagnosis or highlight genetic weaknesses specific to the disease that may lead to the development of new treatments.
Professor Tutt leads a clinical trial called TNT (Triple Negative Trial), which aims to work out which of two chemotherapy drugs (carboplatin and docetaxcel) works best for women with the disease. As this is the only current option for these patients, it’s vital that doctors know which drug to prescribe.
Initial data from this study, presented at a 2014 conference in San Antonio, Texas, showed that there wasn’t any difference in benefit between the two drugs, meaning it’s unlikely to have any impact on treatment. However, the really interesting result came when they began to divide patients into smaller sub-groups. For patients who tested positive for a faulty BRCA gene, the drug carboplatin gave a significant benefit over docetaxel. This shows how even refining our definition of triple negative breast cancer by one degree (faulty BRCA or not) could help guide treatment choice.
Improving the accuracy of diagnosis
As mentioned above, there is an urgent need to find out what sets triple negative breast cancer apart from other types of the disease. Not only will this improve diagnosis but it will also pinpoint its weaknesses that may be able to be targeted with drugs. Professor Tutt’s research has highlighted that different diagnostic tests currently used by clinicians don’t always pick up triple negative cases, which may lead to patients not receiving the most effective treatment.
And finally, the team’s most recent discovery showed how “genomic scars” in the DNA of triple negative tumours could be used to improve diagnosis and treatment.
We are continuing to support the research of Professor Tutt and his team at King’s College London so that more advances can be made in the diagnosis and treatment of triple negative breast cancer. One day, this research may well redefine the way we think about this form of the disease and lead to the development of some much needed targeted treatments.