Inhibitory effect of topical applications of nondenatured soymilk on the formation and growth of UVB-induced skin tumors

• Published in: Oncology research Vol. 14; no. 7-8; p. 387
• Main Authors: Huang, Mou-Tuan, Xie, Jian-Guo, Lin, Connie B, Kizoulis, Menas, Seiberg, Miri, Shapiro, Stanley, Conney, Allan H
• Format: Journal Article
• Language: English
• Published: United States 2004
• Subjects: Administration, Topical; Animals; Apoptosis; DNA Damage; Female; Hot Temperature; Mice; Mice, Hairless; Neoplasms, Experimental; Risk Factors; Skin Neoplasms - etiology; Skin Neoplasms - prevention & control; Skin Neoplasms - veterinary; Soy Milk - administration & dosage; Soy Milk - pharmacology; Swine; Ultraviolet Rays - adverse effects
• ISSN: 0965-0407; 1555-3906
• DOI: 10.3727/0965040041292350

Treatment of female SKH-1 hairless mice with ultraviolet B light twice a week for 20 weeks resulted in a population of tumor-free mice with a high risk of developing skin tumors during the next several months in the absence of additional UVB treatment (high-risk mice). Topical applications of nondenatured soymilk but not heat-denatured soymilk once a day, 5 days a week to these high-risk mice inhibited the formation and growth of skin tumors. Similar topical applications of soybean trypsin inhibitor or Bowman-Birk inhibitor also inhibited the formation and growth of skin tumors, but these agents were less active than nondenatured soymilk. Treatment of miniswine skin with nondenatured soymilk once a day for 5 days prior to UVB irradiation reduced or completely eliminated UVB-induced formation of thymine dimers and apoptotic cells in the epidermis. These data suggest that nondenatured soymilk could be applied to humans to prevent sunlight-induced skin damage and to reduce the risk of skin tumor formation and progression.