Omega-3, the fatty acid found in oily fish, could be combined with a commonly used anesthetic to develop drugs to treat breast cancer, according to researchers. Compounds of omega-3 fatty acids and propofol reduce the ability of breast cancer cells to develop into malignant tumours, inhibiting cancer cell migration by 50% and significantly reducing their metastatic activity. These new compounds could be developed into a new family of anti-cancer drugs.

Dr Rafat Siddiqui, from the Methodist Research Institute and Indiana University studied the effect of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) combined with propofol on a breast cancer cell line in vitro. Omega-3 fatty acids such as DHA and EPA have a minimal effect on cancer cells when applied alone. Propofol is a potent anti-oxidant known to inhibit cancer cell migration by only 5-10%.

The results of the study show that propofol and DHA or EPA have a much more significant effect on cancer cells when used in combination, as conjugates, than when used alone. The conjugates inhibit cancer cell adhesion by 15% and 30% respectively, reduce cell migration by 50% and increase apoptosis (cancer cell death) by 40%.

“These results suggest that the novel propofol-DHA and propofol-EPA conjugates reported here may be useful for the treatment of breast cancer,” conclude Siddiqui and colleagues.

Fatty acids are often attached to drugs, because they facilitate the absorption of the drugs by the cells. Siddiqui and colleagues explain that DHA and EPA might have had this effect on propofol. They add, “It is possible that these conjugates provide a mechanism whereby propofol can be retained in cell membranes for a longer duration and therefore enhance its anticancer effects”.

Breast Cancer Research 2005, 7:R645-R654