• 8/25/2006
  • Scotland
  • Ian Johnston
  • news.scotsman.com

PROBIOTIC bacteria might be able to prevent a deadly form of throat cancer which kills 500 people a year in Scotland, according to new research by Dundee University scientists.

They discovered that the kind of bacteria living in the throats of people with a disease called Barrett’s Oesophagus, which increases the risk of cancer by up to 125 times, was significantly different from the “flora” found in healthy people.

Those with the disease were found to have one particular kind of bacteria, an unusual form of campylobacter, which has been linked with cancer of the oesophagus in animals.

The researchers now plan to investigate whether the use of probiotics, prebiotics or a combination of the two called synbiotics can change the make-up of the bacteria and prevent the genetic damage that results in cancer.

Cancer deaths resulting from Barrett’s Oesophagus have been increasing in Europe over the last three decades and in the UK it has risen from the 20th most common type of cancer death to the seventh most common.

Dr Sandra MacFarlane, an expert in the bacteria which lives inside the human digestive tract, carried out a study which tested the microflora found in the throats of seven Barrett’s patients and seven healthy people.

“We found in the Barrett’s patients there was a greater species diversity of bacteria, but the most important thing we found was a significant difference in numbers of campylobacter,” she said.

“Fifty-seven per cent of Barrett’s patients had them in the distal oesophagus, the area where it goes down in the stomach, and there was none in the controls.

“The thing about this bacteria was they were not the normal campylobacter that causes food poisoning. They were an atypical kind that have been linked to enteritis, dental infections and biliary tract infections.

“They produce nitrosamines and these can cause DNA damage. It has been shown in animals if you give them nitrosamines they can produce cancer in the oesophagus.

Dr MacFarlane, who is working with Dr John Dillon, a consultant gastro-enterologist who treats people with Barrett’s, said they were now looking to confirm a link between the bacteria and cancer in humans.

“If we found there was something, we could then maybe treat the Barrett’s at an early stage and stop the progression to the cancer,” she said.

“Various studies would need to be done to see what probiotics or synbiotics were actually effective against them and to see if we can combat it. We could maybe change the bacteria.

“There might be some way of modulating the system, but we have no idea what probiotics would do, whether there would be any interaction.”

Barrett’s Oesophagus is a complication of gastro-oesophageal reflux disease (Gord).”About 10 per cent of those patients, who have a chronic condition – they have acid coming up all the time – will get Barrett’s,” Dr MacFarlane said.”And with Barrett’s, there is an increased risk, 30 to 125-fold, of getting cancer.”

Doctors currently try to treat Gord and prevent Barrett’s using drugs to prevent the production of as much stomach acid. Surgery can also be used to try to prevent the reflux problem.