Fish fat find

A fatty acid from fish may help prevent a pre-cancerous condition from developing further. A high consumption of fish is associated in some studies with a reduced risk of oesophageal cancer. The n-3 fatty acid eicosapentaenoic acid (EPA) inhibits an enzyme that is associated with the cancer.

“Regular, relatively small doses of EPA produced an effect in human patients”, said Professor Ian Johnson of the Institute of Food Research. “A higher or more prolonged level of supplementation may have a role to play in correcting pre-cancerous changes in cells and tissues”.

Oesophageal cancer rates are increasing faster than any other malignancy. The prognosis for patients is poor as it is usually diagnosed at an advanced stage. The average survival time is less than a year.

Far better then to find ways to prevent it developing.

Most oesophageal cancers arise from a condition called Barrett’s oesophagus. The enzyme cyclo-oxygenase (COX)-2 is upregulated in both Barrett’s oesophagus and oesophageal cancer. The focus of number of trials is therefore to inhibit COX-2.

In the current study, supplementation with EPA over six months did significantly decrease COX-2 levels in Barrett’s oesophagus patients. There was no clear evidence that EPA had any effect on cell proliferation, another pre-cancerous change, but it is difficult to measure proliferation in Barrett’s biopsies.

“Our results provide a good reason for further studies into the anticancer effects of fish oils”, said Professor Johnson.

The research was conducted in collaboration with the Norfolk and Norwich University Hospital and was funded by IFR’s Core Strategic Grant from the Biotechnology and Biological Sciences Research Council with support from the NHS and SLA Pharma.

(Source: American Journal of Clinical Nutrition: Institute of Food Research: July 2008)