Finding the genes behind oesophageal cancer

Scientists at QIMR Berghofer Medical Research Institute have unlocked more clues to Australia’s fastest rising cancer.

Senior authors Professor David Whiteman and Associate Professor Stuart MacGregor co-led an international team with researchers from the Fred Hutchinson Cancer Research Center in the US, which conducted the first genome-wide association study of oesophageal adenocarcinoma.

They identified three new genes linking the reflux condition Barrett’s oesophagus and oesophageal adenocarcinoma (OAC).

“This tells us that Barrett’s and OAC are even more closely linked than we previously thought,” Professor Whiteman said.

“This finding gives us an opportunity to look for targets for drugs which might be used to prevent or treat cancers of the oesophagus.”

Oesophageal adenocarcinoma (OAC) is the fastest rising cancer in Australia and is on the increase across the globe. It is found predominantly in men and known risk factors include acid reflux, obesity and smoking.

Some people who suffer from reflux or heartburn go on to develop the gastro-oesophageal condition Barrett’s oesophagus. Estimates vary, but up to about 5% of people with Barrett’s will eventually develop OAC, compared with less than 1% of the general population.

“We already knew that Barrett’s is a pre-cursor to this type of cancer, and had strongly suspected a genetic component to the conditions. But these findings suggest that the key genes influencing a person’s risk of Barrett’s and OAC are the same,” Professor Whiteman said.

“Ultimately this research could lead to a way to screen people for the high-risk genes, and perhaps modify their risk of developing both Barrett’s and OAC.

“In the meantime though, it is important to remember that the biggest risk factors by far for this cancer are still acid reflux, obesity and smoking and these are all factors we can modify,” Professor Whiteman said.

This study used samples provided by the international collaborative group BEACON – The Barrett’s Oesophagus and Adenocarcinoma Consortium. Genotyping was conducted at the Fred Hutchinson Cancer Research Center in Seattle, USA, and analyses were performed at QIMR Berghofer and Fred Hutchinson.

QIMR Berghofer was recently given $2.4 million in Federal funding from the NHMRC to bring together Australia’s major oesophageal cancer research teams, in a Centre of Research Excellence.

This study features in the latest issue of Nature Genetics and can be found at http://dx.doi.org/10.1038/ng.2796

About OAC: About 700 Australians are diagnosed with OAC each year and the prognosis is grim. Seven in 10 patients will die within five years of diagnosis.

About Barrett’s oesophagus : Barrett’s oesophagus is a condition in which the oesophagus – the muscular tube that carries food and saliva to the stomach – changes, so that some of its lining is replaced by a type of tissue similar to that normally found in the intestine.