In a significant breakthrough, published last week, scientists prove for the first time that breast cancer stem cells, the driving force of a tumour, can be targeted in cells from patients; an approach that could increase the chances of survival for women with aggressive breast cancers.  

In findings released last week in the Clinical Cancer Research journal, Manchester scientist Dr Rob Clarke, funded by leading medical research charity Breast Cancer Campaign, has proved for the first time that breast cancer stem cells taken directly from patients can be successfully targeted to treat the disease. Stopping breast cancer stem cells could reduce the chance of tumours surviving treatments, coming back and spreading to other parts of the body such as the bones, liver or brain.  

In the study, Dr Clarke, based at the University of Manchester and his team of scientists isolated 19 breast cancer stem cell samples from 16 patients with invasive and advanced breast cancer, six of which were HER-2 positive. They discovered that a molecule called Interleukin-8 (IL-8) was found in patients with more breast cancer stem cells, and played a significant role in controlling their activity. When this molecule IL-8 is blocked in HER2-positive types of breast cancer, lapatinib, a drug that cancer specialists currently use to target advanced HER-2 positive breast cancer, a particularly aggressive type of the disease, became even more effective at stopping the activity of cancer stem cells.  

Around 50,000 people are diagnosed with breast cancer every year in the UK and 12,000 women still die. Around 30 per cent, 15,000 of those diagnosed, have HER-2 positive breast cancer but currently only have a small number of treatment options so new ways to treat it are needed. Dr Rob Clarke's findings give hope in the form of new treatments which could knock out the cancer stem cells responsible for breast cancer recurring and spreading, therefore saving lives.   

Although this research focused on the slightly rarer, but often more aggressive, HER-2 positive form of breast cancer, Dr Clarke's new approach demonstrates that targeting the molecule IL-8 has the potential to stop all types of breast cancer recurring and spreading as well as other cancers.  

Dr Rob Clarke commented on the new findings, "This research is in its early stages, but is hugely exciting in showing real promise for women with breast cancer. As targeted drugs similar to those used in this study have already been tested in patients, the time it takes to bring these findings into clinical trials will be significantly reduced. Targeting breast cancer stem cells takes us one step closer to better clinical options for women diagnosed with the disease and we're eagerly looking forward to what the next stages of our investigation will bring."  

"Breast cancer stem cells hold the key to vital new approaches and treatments to help us beat breast cancer once and for all. We're making progress every day but we can only get there with charities like Breast Cancer Campaign and their support of our work."  

Baroness Delyth Morgan, Breast Cancer Campaign's Chief Executive, said, "This research is a real game changer in the fight against breast cancer. Dr Clarke has taken a crucial new step by proving that breast cancer stem cells can be targeted which will improve treatments in the future and extend women's lives. At Breast Cancer Campaign we fund only the very best research and this is one of those stand-out projects; bringing real patient benefit from the best and brightest minds working to tackle breast cancer. We're hoping to see this work changing the treatment landscape in the next decade."  

Dr Rob Clarke was the first breast cancer researcher in the UK to be awarded a Breast Cancer Campaign Scientific Fellowship. Together with co-author of Clinical Cancer Research journal's new findings, Dr Gillian Farnie, he has been funded by the charity's partnership with Asda through its Tickled Pink campaign which contributes £1 million to breast cancer stem cell research in the UK.

What is a breast cancer stem cell?

The breast contains lots of different types of cells, all coming from a single type of breast cell known as a stem cell. These stem cells play a crucial role as they're always present and continue to divide to produce other types of breast cells that are required over a lifetime. While current treatments kill the cells in a breast tumour it's thought they fail to kill the cancer initiating stem cells which then continue to divide, forming a new breast tumour. By killing the tumour's root, the tumour can't regrow.