An enhanced apoptosis and a reduced angiogenesis are associated with the inhibition of lung colonisation in animals fed an n-3 polyunsaturated fatty acid-rich diet injected with a highly metastatic murine melanoma line.
Both epidemiological and experimental studies indicate that dietary n-3 PUFA inhibit carcinogenesis and tumour growth. Metastatic diffusion has also been found to be affected in animals fed diets containing purified n-3 PUFA or fish oil. In the present study, we investigated whether the metastatic diffusion of a highly metastatic variant (F10-SR cells) isolated from the B16 melanoma F10 line was affected by feeding host animals a diet containing 5 % fish oil. In these animals, compared with those fed a diet containing 5 % maize oil, there was a reduced number of metastatic pulmonary colonies. The immunohistochemical analysis of appropriate markers revealed that the antimetastatic effect of dietary n-3 PUFA was not related to a reduction of proliferation, but rather to an enhanced apoptotic activity. The reduction of von Willebrand factor immunoreactivity found in pulmonary colonies of F10-SR cells grown in fish oil-fed animals indicates that a decrease of angiogenesis contributes to the antimetastatic effect of dietary n-3 PUFA. This conclusion stands in spite of the higher expression of vascular endothelial growth factor observed in pulmonary colonies grown in fish oil-fed animals.
Mannini
Antonella
A
Department of Experimental Pathology and Oncology, University of Florence, Viale G.B. Morgagni 50, Florence, Italy.
Kerstin
Nadja
N
Calorini
Lido
L
Mugnai
Gabriele
G
Ruggieri
Salvatore
S
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D004042:Dietary Fats, Unsaturated / Q000627:therapeutic use*; D015525:Fatty Acids, Omega-3 / Q000627:therapeutic use*; D005260:Female; D008175:Lung Neoplasms / Q000098:blood supply / Q000473:pathology / Q000517:prevention & control* / Q000556:secondary; D008546:Melanoma, Experimental / Q000098:blood supply / Q000473:pathology / Q000556:secondary*; D051379:Mice; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000473:pathology / Q000517:prevention & control*
D004042:Dietary Fats, Unsaturated; D015525:Fatty Acids, Omega-3