Systemic treatment with n-6 polyunsaturated fatty acids attenuates EL4 thymoma growth and metastasis through enhancing specific and non-specific anti-tumor cytolytic activities and production of TH1 cytokines.
Recently, there has been a great interest in the effects of different types of n-6 polyunsaturated acids (n-6 PUFAs) upon the immune system and cancer development. However, the effects of n-6 PUFAs are still controversial and as yet undefined. The present study aimed to investigate the anti-tumor effects of n-6 PUFAs against EL4 thymoma and the associated immune mechanisms. To this, sesame oil, a vegetable oil enriched with n-6 PUFAs, or free linoleic acid (LA) were administered intraperitoneally into C57BL/6 mice before and after challenge with EL4 lymphoma cells. Treatment with either sesame oil or LA attenuated the growth and metastasis of EL4 lymphoma. The anti-tumor effect of LA was superior to that of sesame oil, and associated with an increase in the survival rate of the tumor-bearing mice. In addition, both sesame oil and LA showed dose-dependent anti-lymphoma growth in vitro. Treatment with LA generated significant increases in the anti-lymphoma cytolytic and cytostatic activities of T cells and macrophages, respectively, and enhanced production of IL-2 and IFN-gamma while decreased production of IL-4, IL-6 and IL-10. In summation, the results suggest that n-6 PUFAs, represented by LA, can attenuate EL4 lymphoma growth and metastasis through enhancing the specific and non-specific anti-tumor cytolytic activities and production of TH1 cytokines. These findings might be of great importance for a proper design of systemic nourishment with PUFAs emulsions for cancer patients.
Salem
Mohamed Labib
ML
Department of Surgery, Section of Surgical Oncology, Holling Cancer Center R313, Medical University of South Carolina, Charleston, SC 29425, USA. salemm@musc.edu
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D016207:Cytokines / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D005260:Female; D019787:Linoleic Acid / Q000494:pharmacology; D008113:Liver Neoplasms / Q000517:prevention & control / Q000556:secondary; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D009362:Neoplasm Metastasis / Q000517:prevention & control; D012715:Sesame Oil / Q000494:pharmacology; D013154:Spleen / Q000166:cytology; D013268:Stimulation, Chemical; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology; D018417:Th1 Cells / Q000187:drug effects / Q000378:metabolism*; D013945:Thymoma / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology; D013953:Thymus Neoplasms / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology
D000970:Antineoplastic Agents; D016207:Cytokines; D005231:Fatty Acids, Unsaturated; D012715:Sesame Oil; D019787:Linoleic Acid