In vivo antitumor activity of hydrophilic arginine-conjugated linoleic acid complex

Although conjugated linoleic acid (CLA) exerted potent antitumor activities in several animal models, application of CLA as a bioactive ingredient has been limited due to its hydrophobicity. This study was designed to determine the antitumor activity of arginine-CLA complex (Arg-CLA), a hydrophilic form of CLA. Mouse forestomach cancer was induced by gavage with benzo(a)pyrene (B(a)P) for 4-weeks prior to Arg-CLA (0.2 and 0.5%) feeding. Complete necropsies were performed to determine the number, size and locations of all the forestomach tumors at 20 weeks post-B(a)P administration. All mice in the B(a)P group developed tumors, and tumor incidences were decreased by 31% and 44% in 0.2% and 0.5% Arg-CLA-fed groups, respectively, whereas no decrease was observed when Arg or corn oil was given alone. Our results suggest that Arg-CLA suppresses mouse forestomach cancer.