Effects of a fish oil-based emulsion on rat hepatoma cell invasion in culture.
OBJECTIVE
Total parenteral nutrition containing a lipid emulsion is often employed after surgical tumor resection. This study investigated the effects of a fish oil-based infusion on rat hepatoma cell invasion.


METHODS
Rat ascites hepatoma cell line AH109A was precultured with a fish oil-based or safflower oil-based emulsion for 48 h. Changes in membranous fatty acid composition were evaluated by gas chromatography. The invasiveness of hepatoma cells was assessed by coculturing with mesentery-derived mesothelial cells. To examine ex vivo effects of the fish oil-based infusion on hepatoma invasion, sera were prepared from rats infused with fish oil- or safflower oil-based emulsion and the effects of these sera were assessed. To clarify the mechanism of inhibition of invasion by the fish oil-based emulsion, the effects of prostaglandin (PG) E(2) and PGE(3) on invasion were examined.


RESULTS
Pretreatment with the fish oil-based emulsion reduced invasiveness without affecting growth compared with the safflower oil-based emulsion. Pretreatment with the sera from rats infused with the fish oil-based emulsion also reduced invasiveness compared with the sera from rats infused with the safflower oil-based emulsion. The addition of PGE(2) eliminated the inhibitory effect of the fish oil-based emulsion, and the addition of PGE(3) reduced the invasiveness of hepatoma cells pretreated with the safflower oil-based emulsion.


CONCLUSIONS
These results suggest that the fish oil-based emulsion may have anti-invasive effects. Changes in the membranous fatty acid composition and consequent changes in the prostaglandins produced may be involved in this inhibitory effect.
Hagi
Akifumi
A
Nutrition Research Institute, Otsuka Pharmaceutical Factory, Inc., Tokushima, Japan. hagiak@otsukakj.co.jp
Nakayama
Mitsuo
M
Miura
Yutaka
Y
Yagasaki
Kazumi
K
D000527:Alprostadil / Q000031:analogs & derivatives / Q000378:metabolism; D000818:Animals; D002455:Cell Division / Q000187:drug effects*; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000737:chemistry; D015232:Dinoprostone / Q000378:metabolism; D005217:Fat Emulsions, Intravenous / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D005395:Fish Oils / Q000494:pharmacology*; D008114:Liver Neoplasms, Experimental; D008297:Male; D009361:Neoplasm Invasiveness; D010289:Parenteral Nutrition, Total; D011897:Random Allocation; D051381:Rats; D012450:Safflower Oil / Q000494:pharmacology
D005217:Fat Emulsions, Intravenous; D005231:Fatty Acids, Unsaturated; D005395:Fish Oils; D012450:Safflower Oil; C033246:prostaglandin E3; D000527:Alprostadil; D015232:Dinoprostone