Researchers from Cardiff University have discovered a protein driving aggressive breast cancer, which they say could be targeted for developing new and improved therapies.

150 new cases of breast cancer are diagnosed in the UK every day, with 23% of cases being reported as preventable.

Professor Matt Smalley, from Cardiff University’s European Cancer Stem Cell Research Institute, said of the discovery: “To achieve better outcomes for people facing this disease, we need to better understand how it develops so we can improve therapies.

“We wanted to understand what drives an aggressive type of breast cancer called triple negative, which is resistant to hormone therapy and occurs in around fifteen percent of breast cancer cases.

“We looked at a protein called LYN, which is involved in keeping cells alive and allowing them to divide, and found that it was no longer properly controlled in aggressive breast cancer cells and could drive the cancer cell growth, spread and invasion.”

The team found that in a subset of triple negative breast cancer cells associated with the BRCA1 gene mutation, the newly discovered protein - LYN - could be switched on and increase cancer cell survival directly as a result of the loss of BRCA1 (a human tumour suppressor gene responsible for repairing DNA).

The researchers also found that interfering with LYN function under experimental conditions killed these BRCA1-mutant cells.

Matt Smalley went on to explain further: “In the future, we could potentially identify patients that have increased levels of LYN or a BRCA1 gene mutation, and design their breast cancer therapy to suit their type of cancer. We could target LYN to improve therapy options for aggressive breast cancer.”