Welsh scientists discover vital clue to breast cancer spread

Cancer Research UK scientists in Wales believe they have made a discovery that could help halt the rapid spread of breast cancer, revealing their findings at the world’s largest breast cancer conference¹.

Dr Wen Jiang and his team in Cardiff studied molecules called tight junctions, which act like zips sealing the gaps between cells in our bodies. They found that patients with fewer of these zips were more prone to breast cancer spread.

And they believe designing therapies to boost the levels of tight junctions could stop breast cancer cells from invading other parts of the body by closing-up their escape routes.

Researcher Professor Robert Mansel, from the University of Wales College of Medicine in Cardiff says: “There are currently very effective methods to treat cancer confined to the breast but treatment becomes more difficult when abnormal cells spread to other parts of the body.

“By understanding how cancer cells escape from a breast tumour we can look at ways to halt the process in its early stages and contain the disease, making it far more manageable.”

Researchers analysed breast tumours taken from 114 women and measured the levels of tight junctions in the tissue. In a six year follow up they assessed each of the women’s health and compared their status to their levels of tight junctions.

They found women whose breast cancer had spread had significantly lower levels of tight junctions in their tumours when compared with women who remained cancer-free after surgery.

Study author Dr Jiang, also from the University of Wales College of Medicine in Cardiff says: “Our new study shows a direct link between the levels of tight junctions and the progression of breast cancer.

“It seems that some patients are more prone to breast cancer spread than others because they have fewer of these zip-like molecules between their cells. Doctors could use this information to predict the likelihood of the disease spreading at diagnosis and strategically plan treatments.”

He adds: “We will now aim to look at ways of increasing the levels of tight junctions to see if this will help control the disease.”

Cancer spreads to other parts of the body when a cell breaks away from the primary tumour and burrows into a surrounding blood vessel to enter the blood stream.

Researchers believe low levels of tight junctions widen the gaps between cells in tumours and blood vessels, making it easier for rogue cancer cells to make their escape.

Professor Robert Souhami, Director of Clinical Research at Cancer Research UK says: “This study provides us with a valuable insight into the molecular basis of breast cancer spread.

“We now need to look at ways to exploit these findings to manage breast cancer more effectively and improve the survival of patients.”

ENDS