The researchers decoded a complete cascade of signals within breast  tumour cells activated by virgin olive oil, and concluded that benefits  include decrease in the activity of the oncogene p21Ras, changes in  protein signaling pathways, stimulation of tumour cell death and  prevention of DNA damage. The study was carried out in an experimental  model and researchers have already begun a new study with human cell  lines.Breast cancer is the most common type of cancer in Western  countries. Research carried out with animal models demonstrate that a  diet rich in fats is directly related to the incidence of cancer. Some  types of fats however can play a protective role against the development  of these tumours. Such is the case of virgin olive oil, rich in oleic  acid, a mono-unsaturated fatty acid, and containing several bioactive  compounds such as antioxidants. A moderate and regular intake of virgin  olive oil, characteristic of the Mediterranean diet, is associated with  low incidences of specific types of cancer, including breast cancer, as  well as with having a protective role against coronary diseases and  other health problems. The study carried out by UAB researchers decoded the mechanisms  operating within the tumour cell and induced by the intake of olive oil,  in comparison to those activated by corn oil, rich in n-6  polyunsaturated fatty acids, which increase the aggressiveness of  tumours.

Scientists demonstrated that virgin olive oil is associated with  higher incidences of benign breast tumours and at the same time with a  decrease in the activity of the p21Ras oncogene, which spurs  uncontrolled cell proliferation and stimulates the growth of tumours. In  addition, olive oil suppresses the activity of some proteins, such as  the AKT, essential for the survival of cells since they prevent  apoptosis, the cell’s “suicide” programme. Between proliferation and  apoptosis in tumour cells, these effects tip the balance towards cell  death, thereby slowing the growth of tumours.Another result obtained by researchers is the protection of DNA in  the cell nucleus. Cells from animals fed a diet rich in virgin olive oil  contained less DNA lesions than those fed a control diet.Scientists of the UAB Breast Cancer Study Multidisciplinary Group  (GMECM) have spent over twenty years working to determine the effects  fats have on breast cancer, and in particular the effects of virgin  olive oil. Previous studies of the group revealed the beneficial effects  of this component of the human diet on the clinical conduct of mammary  tumours and on their histological grade (malignancy). Scientists also  described several molecular mechanisms producing these effects and in  2004 the same group was the one to identify the four genes involved in  the effects dietary fats have on experimental breast cancer. The  mechanism recently discovered was published in the journal Carcinogenesis.