5-Methoxypsoralen, the melanogenic additive in sun-tan preparations, is tumorigenic in mice exposed to 365 nm u.v. radiation.
5-Methoxypsoralen (5 MOP), the melanogenic component present in several suntan preparations was synthesized and tested by topical applications in inbred XVII nc/Z albino mice combined with 365 nm irradiation with the aim of establishing the relative carcinogenic activity of this compound, as compared to 8-methoxypsoralen (8 MOP) and psoralen. 85% of the animals developed tumors and 25% had multiple tumors. Additional treatment with 12-O-tetradecanoylphorbol-13-acetate raised the tumor incidence to 100%. Tumors caused by 5 MOP show much longer latent periods than those induced by psoralen and 8 MOP. Most of the tumors were rapidly growing squamous cell carcinomas giving metastases in 20% of the animals. The possible long-term effects that might follow the use of 5 MOP in humans are discussed.
D000078223:5-Methoxypsoralen; D000818:Animals; D002273:Carcinogens; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced; D004260:DNA Repair / Q000187:drug effects; D005260:Female; D008297:Male; D008730:Methoxsalen / Q000633:toxicity*; D051379:Mice; D009381:Neoplasms, Radiation-Induced / Q000503:physiopathology*; D012878:Skin Neoplasms / Q000139:chemically induced*; D014466:Ultraviolet Rays
D002273:Carcinogens; D000078223:5-Methoxypsoralen; D008730:Methoxsalen