Dietary omega-3-polyunsaturated fatty acids prevent the development of metastases of colon carcinoma in rat liver.
BACKGROUND
Fish oil consisting of omega-3 polyunsaturated fatty acids (PUFA) seems to reduce the incidence of colon cancer. The effect of PUFAs on metastasis of colon carcinoma is still unclear.


OBJECTIVE
The study was designed to examine the effects of a diet rich in omega-3-PUFAs on a model of colorectal metastasis.


METHODS
Thirty animals (WAG/Rij) were randomly assigned to receive an omega-3 diet or a control diet to evaluate their effect on tumor growth. The target male rats (WAG/Rij) were fed a diet containing 15% omega-3-fatty acids three days before and 28 days after intervention and the control rats received 15% coconut oil at the same time points. CC 531 cells, a moderately differentiated colon adenocarcinoma, were injected into the spleen of each rat. After 28 days of diet, animals were sacrificed. The tumor growth was evaluated macroscopically and microscopically in liver tissue. The tissue was examined after immunostaining and the use of monoclonal antibodies.


RESULTS
PUFAs decreased the index of tumor load from 1.54 in the controls to 0.79 in the treatment group (P = 0.036). While 69.2% of the control animals were tumor positive, only 21.4% of the target animals showed tumor after omega-3-fatty acid (P < 0.05).


CONCLUSIONS
We could show that omega-3-fatty acids may decrease malignant metastatic tumor growth in the liver.
Gutt
Carsten N
CN
Dept. of General, Visceral and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
Brinkmann
Lars
L
Mehrabi
Arianeb
A
Fonouni
Hamidreza
H
Müller-Stich
Beat P
BP
Vetter
Gregor
G
Stein
Jürgen M
JM
Schemmer
Peter
P
Büchler
Markus W
MW
D000818:Animals; D002277:Carcinoma / Q000473:pathology*; D003110:Colonic Neoplasms / Q000473:pathology*; D004032:Diet; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D008113:Liver Neoplasms / Q000453:epidemiology / Q000473:pathology / Q000556:secondary*; D008297:Male; D009362:Neoplasm Metastasis / Q000517:prevention & control; D011897:Random Allocation; D051381:Rats; D011919:Rats, Inbred Strains
D015525:Fatty Acids, Omega-3