Carp antitumor activity

First, I examine the antitumor activity of the oral administration of two fish oils (carp oil and tuna oil) in sarcoma 180-bearing mice. Carp oil and tuna oil (0.2 and 0.4 ml/mouse) had no effects on tumor growth Table (2) . 

Carp (Cyprinus carpi ) has been used in Korea, China and Japan as a health food source. In ancient Chinese medicine, carp was eaten as diuretic, and as a remedy for eye fatigue. In Japan, carp meat and blood have traditionally been eaten as a tonic. Although it has recently been thought that carp extract has antitumor activity, the basis for this hearsay is unclear. Therefore, to clarify whether carp extract has antitumor effects, the antitumor effect of carp extract, and the combined effect of 5-FU plus carp extract on antitumor activity and side effects were investigated in sarcoma 180-bearing mice. 

To characterize the antitumor and/or antimetastatic activities, the effects of carp oil and oleic acid on DNA synthesis in LLC cells, adherence of LLC cells to human adult dermal microvascular endothelial cells (HMVEC), and Matrigel-induced angiogenesis (in vitro and in vivo) were tested. Carp oil inhibited DNA synthesis in LLC cells at 100 and 1000 pg/mL, but not at 0.1 to 10 pg/mL Table (10) . Oleic acid inhibited DNA synthesis in LLC cells at 1000 pM Table (11) . Carp oil inhibited the Matrigel-induced tube-like network formation of HMVEC at 1000 pg/mL, but not at 0.1 to 100 pg/mL Table (10) . 

On the other hand, the inhibitory actions of oleic acid on metastasis in the liver and metastatic tumor growth in the liver, cannot be explained by the effects of DNA synthesis in LLC cells, and microvascular endothelial cells, or the adherence of LLC cells to the microvascular endothelium rather, these inhibitory actions by oleic acid are partly attributable to the inhibition of the angiogenesis induced by tumors. In conclusion, it seems likely that the antitumor and antimetastatic activities of carp oil may be partly ascribed to a fatty acid, oleic acid, as an active substance. However, the antitumor and antimetastatic effects of carp oil are insufficiently by themselves to explain the action of oleic acid. Further work is in progress to identify the active substance(s) in carp oil. 

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