title: Effects of high-fat diets rich in either omega-3 or omega-6 fatty acids on UVB-induced skin carcinogenesis in SKH-1 mice.
abstract: Our previous studies reported that caffeine or voluntary exercise decreased skin tumor multiplicity, in part, by decreasing fat levels in the dermis. These data suggest that tissue fat may play an important role in regulating ultraviolet light (UV) B-induced skin tumor development. In the present study, we explored the effects of high-fat diets rich in either omega-3 or omega-6 fatty acids on UVB-induced skin carcinogenesis. SKH-1 mice were irradiated with 30 mJ/cm(2) of UVB once a day, two times per week for 39 weeks. During UVB treatment, one group of mice was given a high-fat fish oil (HFFO) diet rich in omega-3 fatty acids and the other group of mice was given a high-fat mixed-lipids (HFMLs) diet rich in omega-6 fatty acids. The results showed that, compared with HFML diet, HFFO treatment (i) increased latency for the development of UVB-induced skin tumors; (ii) decreased the formation of papilloma, keratoacanthoma and carcinoma by 64, 52 and 46%, respectively and (iii) decreased the size of papilloma, keratoacanthoma and carcinoma by 98, 80 and 83%, respectively. Mechanistic studies with antibody array revealed that compared with HFML diet, administration of HFFO to the mice significantly decreased the UVB-induced increases in the levels of TIMP-1, LIX and sTNF R1 as well as other several proinflammatory cytokines and stimulated the UVB-induced apoptosis in the epidermis. Our results indicate that omega-3 fatty acids in HFFO diet have beneficial effects against UVB-induced skin carcinogenesis, and these effects may be associated with an inhibition on UVB-induced inflammatory response.
authors.affiliation: Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
authors.forename: You-Rong
authors.initials: YR
authors.lastname: Lou
authors.forename: Qing-Yun
authors.initials: QY
authors.lastname: Peng
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Medvecky
authors.forename: Yong
authors.initials: Y
authors.lastname: Lin
authors.forename: Weichung Joe
authors.initials: WJ
authors.lastname: Shih
authors.forename: Allan H
authors.initials: AH
authors.lastname: Conney
authors.forename: Sue
authors.initials: S
authors.lastname: Shapses
authors.forename: George C
authors.initials: GC
authors.lastname: Wagner
authors.forename: Yao-Ping
authors.initials: YP
authors.lastname: Lu
mesh_terms: D000818:Animals; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage*; D005260:Female; D051379:Mice; D008812:Mice, Hairless; D009381:Neoplasms, Radiation-Induced / Q000209:etiology / Q000517:prevention & control*; D012878:Skin Neoplasms / Q000209:etiology / Q000517:prevention & control*; D014466:Ultraviolet Rays
chemical_list: D004042:Dietary Fats, Unsaturated; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6