Olive oil 'cuts cancer risk'
2005-01-10 08:46
Washington - Olive oil can help fight breast cancer, a discovery that researchers said in a study out on Sunday could guide the development of related treatment.
"Our findings underpin epidemiological studies that show that the Mediterranean diet has significant protective effects against cancer, heart disease and ageing," said the study's lead author Javier Menendez, of Northwestern University's Feinberg medical school in Chicago.
Researchers showed in a series of laboratory experiments on breast cancer cells that oleic acid, found in olive oil, dramatically cuts the levels of a cancer-promoting gene called Her-2/neu (also known as erb B-2), according to Menendez.
High levels of the gene occur in over a fifth of breast cancer patients and are associated with highly aggressive tumours that have a poor prognosis, according to findings reported in the January 10 Annals of Oncology.
'Boosted an antibody treatment'
Oleic acid suppressed the gene, and other tests showed that it boosted an antibody treatment trastuzumab (Herceptin), which targets the gene and has helped to prolong the lives of many breast cancer patients, the researchers said.
Menendez said the findings should not only help in understanding the molecular mechanisms by which individual dietary fatty acids regulate the malignant behaviour of breast cancer cells, but also suggested eating oleic acid may help Herceptin work in breast cancer patients with the Her-2/neu gene.
"To our knowledge this is the first report that a dietary monounsaturated fatty acid previously suggested to be protective against breast cancer significantly down-regulates the expression of Her-2/neu, cutting it by up to 46%. Her-2/neu is one of the most important oncogenes in breast cancer," said Menendez.
"In our tests, oleic acid's inhibition of Her-2/neu synergistically interacted with Herceptin-based immunotherapy by promoting the death of breast cancer cells exhibiting high levels of the oncogene.
"Additionally, alongside the sensitising effect of oleic acid on the efficacy of Herceptin we found it increased the expression of a protein (p27Kip1), a tumour suppresser protein, which is implicated in the development of resistance to Herceptin treatment."