Conjugated dienoic linoleate: a polyunsaturated fatty acid with unique chemoprotective properties

Conjugated dienoic linoleate (CLA), a linoleic acid derivative, has received considerable attention as a chemoprotective agent in the past few years because it has been shown experimentally to inhibit rat mammary tumorigenesis, mouse forestomach neoplasia, and mouse skin carcinogenesis. CLA has several unique structural and functional properties resulting in chemical and physiological effects that are different from those of all-cis, nonconjugated polyunsaturated fatty acids. In turn, these unique qualities appear to modulate cellular processes involved in carcinogenesis. This review will introduce the chemical background of conjugated dienoic linoleate, examine findings describing its chemoprotective qualities, present possible mechanisms of chemoprotection, and correlate the possible significance of dietary CLA modulation to carcinogenesis to humans.