Inhibitory effects of purified eicosapentaenoic acid and docosahexaenoic acid on growth and metastasis of murine transplantable mammary tumor.

We studied the effects of purified linoleic acid, eicosapentaenoic acid(EPA) and docosahexaenoic acid (DHA) on mammary tumor MM48 the transplanted into C3H/He mice. The growth of the primary tumor was significantly inhibited in EPA- and DHA-treated groups as compared with control and/or linoleic acid-treated groups (p < 0.05). The number of metastatic tumors in the lungs tended to be inhibited in the EPA- and DHA-treated groups and promoted in the linoleic acid-treated group, as compared with the control group, but not to a statistically significant extent. The EPA-treated group survived significantly longer than the control group (p = 0.002), while the DHA-treated group survived longer than the control group although the difference was not significant (p = 0.070). However, there was no significant difference between EPA- and DHA-treated groups on primary tumor growth, number of lung metastases or survival time of animals.