N-3 polyunsaturated fatty acids accentuate B16 melanoma growth and metastasis through suppression of tumoricidal function of T cells and macrophages.
BACKGROUND
The antitumor effects of the n-3 polyunsaturated fatty acids (PUFAs) are still controversial and as yet undefined.


METHODS
EPA-28, a fish oil enriched with n-3 PUFAs including eicosapentaenoic and docosahexaenoic acids, was administered subcutaneously into C57BL/6 mice before and after subcutaneous inoculation of B16 melanoma cells. The effects of EPA-28 on the antitumor activities of T cells and macrophages were investigated.


RESULTS
The treatment of the mice with EPA-28 before and after the tumor inoculation enhanced the growth and metastasis of B16 melanoma and decreased the survival rate of the tumor-bearing mice. The treatment also decreased the number of CD4+ T cells in the spleen and tumor draining lymph nodes on day 14 after the tumor inoculation. Moreover, EPA-28 suppressed the antimelanoma cytolytic activity of T cells and macrophages of the tumor-bearing mice.


CONCLUSIONS
The results suggest that EPA-28 treatment increased both the growth and metastasis of B16 melanoma cells by suppressing the cytolytic function of both T cells and macrophages.
Salem
M L
ML
Department of Immunology, Kyushu University, Fukuoka, Japan. mohamed-84@hotmall.com
Kishihara
K
K
Abe
K
K
Matsuzaki
G
G
Nomoto
K
K
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D005260:Female; D005395:Fish Oils; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D008546:Melanoma, Experimental / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D015996:Survival Rate; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects* / Q000276:immunology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D016207:Cytokines; D005231:Fatty Acids, Unsaturated; D005395:Fish Oils; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid