Evaluation of chemopreventive effect of dietary selenium-rich egg on mouse skin tumor induced by 2′-(4-nitrophenoxy)oxirane and 12-O-tetradecanoylphorbol-13-acetate

• Published in: Carcinogenesis (New York) 1995-12, Vol.16 (12), p.2995-2998
• Main Authors: Hwan Oh, Sang, Park, Kwang-Kyun, Kim, So Young, Lee, Kum Joo, Lee, Young-Ho
• Format: Article
• Language: English
• Subjects: Animals; Anticarcinogenic Agents - administration & dosage; Anticarcinogenic Agents - therapeutic use; Anticarcinogenic Agents - toxicity; Biological and medical sciences; Carcinogenesis, carcinogens and anticarcinogens; Carcinogens - antagonists & inhibitors; Carcinogens - toxicity; Chemical agents; Diet; Eggs; Epoxy Compounds; Glutathione Peroxidase - blood; Glutathione Peroxidase - metabolism; Male; Medical sciences; Mice; Mice, Inbred ICR; Papilloma - chemically induced; Papilloma - prevention & control; Selenium - administration & dosage; Selenium - therapeutic use; Selenium - toxicity; Skin Neoplasms - blood; Skin Neoplasms - chemically induced; Skin Neoplasms - prevention & control; Tetradecanoylphorbol Acetate - antagonists & inhibitors; Tetradecanoylphorbol Acetate - toxicity; Tumors
• ISSN: 0143-3334; 1460-2180
• DOI: 10.1093/carcin/16.12.2995

Chemopreventive effect of dietary selenium (as sodium selenite or as Se-rich egg) on mouse skin tumor induced by topical application of 2′-(4-nitrophenoxy)oxirane (NPO) as tumor initiator and 12-O-tetradecanoylphorbol-13-acet-ate (TPA) as tumor promoter was evaluated in relation to the dietary source and levels of selenium. Selenium supplementation (0.3 p.p.m.) to the basal diet (0.07 p.p.m. Se) as sodium selenite or as Se-rich egg brought about a 40 or 37% reduction respectively, in the incidence of papilloma formation at 12 weeks after NPO treatment. Tumor yield (number of papillomas per mouse) at 14 weeks after NPO treatment in the basal diet group, basal diet supplemented with 0.3 p.p.m. Se as sodium selenite group and basal diet supplemented with 0.3 p.p.m. Se as Se-rich egg group were 7.5 ± 2.1, 2.7 ± 2.3 and 4.1 ± 3.5 respectively. Dietary supplementation of 1.0 p.p.m. Se as Se-rich egg to the basal diet reduced the incidence and the multiplicity of papillomas during the early phase of promotion (11 weeks) but its antitumor activity decreased thereafter, indicating that the accumulation of tissue selenium above the saturated level may not be beneficial. Selenium concentrations in blood, liver and skin tissue of mice in basal diet group (0.33 ± 0.02, 0.54 ± 0.10 and 0.21 ± 0.03 p.p.m. respectively) increased significantly (P