The role of fatty acids and eicosanoid synthesis inhibitors in breast carcinoma.

We have reviewed the literature concerning the role of fatty acids and eicosanoid synthesis inhibitors in breast carcinoma. The omega-6 polyunsaturated fatty acids (PUFAs), primarily linoleic acid, promote breast cancer tumorigenesis and tumor cell proliferation directly and indirectly via increased synthesis of cyclooxygenase- and lipoxygenase-catalyzed products. The omega-3 PUFAs, primarily docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), suppress breast carcinoma tumorigenesis and tumor cell proliferation, although the effect of DHA may be partly ascribed to increased amounts of EPA derived from DHA. Both cyclooxygenase and lipoxygenase inhibitors suppress tumorigenesis and/or tumor proliferation, with the latter being more active. Thus, arachidonic acid-derived eicosanoids play an important role in breast cancer, and the balance of the various eicosanoids may be a critical determinant of cell proliferation. However, the exact mechanism by which fatty acids and eicosanoid synthesis inhibitors exert stimulatory and inhibitory effects on breast carcinoma is still not well understood.