Many genetic factors influence how breast cancer develops and progresses. One such gene known to be involved in breast cancer progression is called HERV-K. The HERV-K gene is present in our cells as a result of viral DNA that entered the human genome millions of years ago, but in normal, healthy cells HERV-K is switched off.
In two thirds of breast cancers, however, the HERV-K gene is active and provides the instructions for cells to produce four distinct proteins, called Env, Gag, Np9 and Rec. While Env has previously been found to be linked to increased risk of breast cancer spreading and reduced chances of surviving the disease, the exact functions of the other three proteins – and their roles in breast cancer growth and development – are unknown.
Dr Sharon Glynn, based at NUI Galway, will lead a three year study to investigate how HERV-K and its associated proteins influence the development and progression of breast cancer. Dr Glynn hopes to uncover whether the four HERV-K proteins could be used as markers to predict whether an individual’s breast cancer is likely to spread.
The team will investigate whether Env and Gag proteins are able to drive tumour growth, and therefore whether they could be potential drug targets. They will reduce the production of these proteins in five different types of breast cancer cell in the lab and assess the impact on cancer cell growth and ability to invade their surroundings.
Dr Glynn will also introduce the proteins Np9 and Rec to healthy breast cells that do not normally produce these proteins, to see whether they cause the healthy cells to behave like cancer cells, and may be involved in the development of breast cancer. This research will help her establish the usefulness of targeting HERV-K therapeutically.
The team will also measure the levels of HERV-K proteins present in tumour samples donated by over 700 breast cancer patients, and analyse patient data to identify any links between the quantities of the four HERV-K proteins and the chances of breast cancer spreading.
Dr Glynn hopes to eventually develop a diagnostic laboratory test that could use HERV-K and its associated proteins as ‘biomarkers’ to predict the likelihood that breast cancer will progress, which could in the future be used to determine the best course of treatment for people diagnosed with the disease.
Dr Sharon Glynn, Lecturer in Pathology at NUI Galway, said:
“Breast Cancer Now’s funding both past and present has been instrumental to the advancement of my group’s breast cancer research. We are delighted that they are supporting our research into the role of HERV-K in breast cancer and believe that this will greatly advance our knowledge, allowing us to more accurately predict patient outcomes, which could lead to improved treatment for breast cancer patients.”
Rachel Leahy, Research Communications Officer at Breast Cancer Now, said:
“Dr Glynn’s research will enhance our understanding of the biological factors that contribute to breast cancer progression and may enable new drugs to be developed to target the HERV-K proteins.
“This study could also lead to the development of new tests to more accurately predict how a person’s breast cancer might progress, and help us better tailor individuals’ treatment to the make-up of their tumour – improving their chances of surviving the disease.”
Around 2,800 women in the Republic of Ireland are diagnosed with breast cancer each year, and nearly 700 women in the country sadly die from the disease each year