Study finds genetic changes that raise risk of breast, prostate and ovarian cancer

Thursday 28 March, 2013

Victorian researchers have taken part in research that has uncovered more than 80 genetic makers that could predict an individual's risk of breast, prostate and ovarian cancers.

The UK-led research, which Cancer Council Victoria and the University of Melbourne have collaborated on, is the largest ever study of its kind and could lead to new treatments, targeted screening and a greater understanding of how these diseases develop.

By studying the DNA of over 100,000 people with cancer and 100,000 people from the general population, researchers found 80 genetic markers that were more common in prostate, breast or ovarian cancers.

The University of Melbourne and the Cancer Council Victoria contributed data from 7500 DNA samples of Australians affected and unaffected by these cancers.

The study, led by Cancer Research UK funded scientists based at the University of Cambridge and The Institute of Cancer Research, looked for genetic markers - called single nucleotide polymorphisms (SNPs) - that may predict the risk of developing cancer.

Each marker is associated with a very small change in risk of cancer, but the one in 100 people who have a large proportion of these errors are five times more likely to develop prostate cancer and three times more likely to develop breast cancer.

Study co-authour Associate Professor Gianluca Severi, Deputy Director of the Cancer Council's Cancer Epidemiology Centre, said the international study was significant because of its size and scope. He believes the findings will help to pinpoint the causes behind these cancers and also ascertain who is most at risk.

"It is the first time so many regions in the genome have been identified and linked to these cancers. These results represent valuable information on why these cancers occur. They can also help us better predict an individual's risk of developing such cancers."

Professor Melissa Southey of the Department of Pathology at the University of Melbourne and her team has conducted genetic analysis of the 7500 samples provided.

"These new markers could provide a more cost effective way of identifying people at high risk whether or not they have a family history," Professor Southey said.

"This information could be used for better screening, prevention and treatment."

From the study, 23 of the genetic markers were found to be related to prostate cancer, taking the total to 78. However, researchers suggest that this is just the tip of the iceberg and there could be over 2,000 such markers that could influence a man's chance of developing the disease.  

For breast cancer the researchers found 49 markers, more than doubling the number that had previously been found. Some of these were found in regions that have been linked to other cancers, suggesting they share underlying mechanisms that can cause cancer.  And, in ovarian cancer nine new markers were found. 

Cancer Council Victoria CEO, Todd Harper, said researchers at CEC had a long-standing relationship with researchers in the UK.

"This study demonstrates how complex cancer is, and how much work there still is to do. I am really pleased that research which CCV is championing, like our Health2020 Program and Prostate Cancer Program, means we are playing an important role globally in the fight against cancer."

Breast cancer is the most common new cancer in Victorian women with over 3700 diagnoses in 2011 (29% of all cancers). Prostate cancer remains the most common new cancer in Victorian men with almost 4700 new diagnoses in 2011 (30% of total cancers)*.


*Data taken from ‘Cancer in Victoria: Statistics and trends 2011' published by the Victorian Cancer Registry.
Updated: 28 Mar, 2013