Today’s front page of The Mirror tells the story of a ‘breast cancer vaccine’ that could be used to treat triple negative breast cancer and save thousands of lives. The idea is an exciting one, but in reality, the research behind the story is still a long way from benefiting patients. Read on to find out more about the work and what Breast Cancer Now is doing in this area.
Tackling triple negative
To determine what type of breast cancer a person has, doctors test for three ‘markers’: oestrogen receptor (ER), progesterone receptor (PR), and multiple copies of the gene HER2. Triple negative breast cancer, as the name suggests, lacks these three markers, and makes up about 15% of all new breast cancer cases, roughly 7,500 women every year.
Unfortunately, unlike other types of breast cancer, there are no targeted treatments available for triple negative breast cancer. This means to treat triple negative tumours, which can sometimes be more aggressive, doctors have to rely upon standard treatments such as surgery, chemotherapy, and radiotherapy, which can have debilitating side effects.
Therefore the hunt is on to find new targeted treatments that people with triple negative breast cancer desperately need to improve their treatment options and chances of survival.
HAGE – a red flag for doctors … and the immune system
Researchers at the University of Nottingham looking at tumour samples from over 1,000 triple negative breast cancer patients made an exciting discovery about a protein called HAGE that was produced in some of these breast tumours.
Two things about HAGE stuck out to them. The first is that patients whose breast tumours had lots of HAGE and received chemotherapy had a better chance of survival than those who had low amounts of HAGE. This suggests that HAGE could be used in the future to predict which triple negative breast cancer patients will benefit from chemotherapy the most.
The second finding however really captured the imagination, and grabbed the front page of The Mirror. When looking at the tumours that had a lot of HAGE, the researchers also found that they had a large number of immune cells called ‘lymphocytes’ present – in short, that the presence of HAGE in these tumours could be attracting the immune system’s interest.
Normally the immune system leaves breast cancer cells alone because they originate from a person’s own body – so to find that the immune system apparently sniffed out the HAGE protein in these tumours is intriguing. This led the researchers to speculate that this could somehow be turned into a treatment known as an “immunotherapy”- if the immune cells are already attracted to these tumours, then maybe they could stimulated to attack them, in the same way they attack germs in the body.
This is an exciting prospect, but at this stage it is just an idea - this treatment isn’t even in existence yet, let alone ready to test in patients. A lot of work needs to be done to confirm these findings, including understanding what might be making HAGE attractive to the immune system.
The outcome of the research most likely to be tested in patients first is actually the first finding – that is, using HAGE to predict which triple-negative breast cancer patients will benefit the most from chemotherapy drugs. This is important because it could ensure that people who will not benefit as much from chemotherapy could have the option to avoid it and so spare them of the side-effects of treatments, which can be severe.
The future of immunotherapies
Getting the immune system to do the hard work of finding and killing breast cancer cells would be a massive development in the treatment of breast cancer, particularly for triple negative breast cancer where new treatments are desperately needed. That’s why Breast Cancer Now is funding several researchers to develop immunotherapies for breast cancer, all with slightly different approaches to get the immune system to search for and destroy breast cancer cells.
The projects we're funding include: improving the safety of a breast cancer immunotherapy; minimising the side effects of a new type of immunotherapy for breast cancer; and finding ways to stimulate the immune system to attack breast cancer cells.
One of the major challenges is finding a molecule in breast cancer cells that will interest the immune system, but that isn’t so widely produced in normal cells that immune cells start attacking the rest of body at the same time. One of our researchers in Cardiff, Prof Andy Sewell, thinks a protein called MAGE-A3 could be a good candidate.
However, the immune system and breast cancer cells have a complicated relationship – whilst some immune cells might be making tumours more susceptible to treatments, other immune cells can help breast tumours to grow and spread. Many of the researchers we fund across the UK and Ireland, including scientists at our Research Unit at King’s College London, are leading the way in unravelling this complexity. They are looking at how breast cancer evades the immune system, how it grows by hijacking the ‘wound healing response’, and how breast cancer uses immune cells to spread to other parts of the body and grow into secondary tumours. All of these projects which will help develop new treatments and improve the ones we have.
Ultimately, if we are to stop people dying from breast cancer, we have to ensure that there are effective treatments that are tailored for every woman and man with all types of the disease, including triple negative breast cancer. It’s a long journey ahead, but research like that featured in the news today, and work that Breast Cancer now is funding, will bring us a step closer to bringing these promising treatments to the thousands of people who need them.