Abstract
Considerable circumstantial evidence has accrued from both experimental animal and human clinical studies that support a role for omega-3 fatty acids (FA) in the prevention of non-melanoma skin cancer (NMSC). Direct evidence from animal studies has shown that omega-3 FA inhibit ultraviolet radiation (UVR) induced carcinogenic expression. In contrast, increasing levels of dietary omega-6 FA increase UVR carcinogenic expression, with respect to a shorter tumor latent period and increased tumor multiplicity. Both omega-6 and omega-3 FA are essential FA, necessary for normal growth and maintenance of health and although these two classes of FA exhibit only minor structural differences, these differences cause them to act significantly differently in the body. Omega-6 and omega-3 FA, metabolized through the lipoxygenase (LOX) and cyclooxygenase (COX) pathways, lead to differential metabolites that are influential in inflammatory and immune responses involved in carcinogenesis. Clinical studies have shown that omega-3 FA ingestion protects against UVR-induced genotoxicity, raises the UVR-mediated erythema threshold, reduces the level of pro-inflammatory and immunosuppressive prostaglandin E2 (PGE2) in UVR-irradiated human skin, and appears to protect human skin from UVR-induced immune-suppression. Thus, there is considerable evidence that omega-3 FA supplementation might be beneficial in reducing the occurrence of NMSC, especially in those individuals who are at highest risk.
Highlights
Considerable interest has been focused on the potential health benefits of omega-3 fatty acids (FA)on a range of human diseases
Lipidomic analysis was performed in a human intervention trial of EPA-rich omega-3 FA, quantifying impact of supplement on eicosanoid levels in skin blister fluid [48]. This showed a significant reduction in the ratio of prostaglandin E2 (PGE2) : PGE3 in ultraviolet radiation (UVR)-exposed skin, accompanied by a reduction in the ratio of the pro-inflammatory and tumor promoting 12-LOX product 12-hydroxyeicosatetraenoic acid (12-HETE): 12-hydroxyeicosapentaenoic acid (12-HEPE), EPA-derived homologue of 12-HETE [48]
Case-control or prospective cohort studies, provided clear evidence that dietary omega-6 FA or omega-3 FA reduces the risk of non-melanoma skin cancer (NMSC)
Summary
Considerable interest has been focused on the potential health benefits of omega-3 fatty acids (FA). While a recent study observed that high levels of serum phospholipid omega-3 FA (a biomarker) were associated with a large increase in the risk of high-grade prostate cancer [17], subsequent systematic review and meta-analysis, including 12 studies of self-reported dietary intake of omega-3 FA and 9 biomarker studies, failed to find an association between omega-3 FA and prostate cancer [18]. These ambiguities require clarification and undoubtedly will require randomized, double-blinded intervention trials. The evidence to support a beneficial outcome for omega-3 FA supplementation on non-melanoma skin cancer (NMSC) is presented
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have