Ae. Peritz et Fp. Gasparro, Psoriasis, PUVA, and skin cancer-molecular epidemiology: The curious question of T -> A transversions, J INV D SYM, 4(1), 1999, pp. 11-16
Citations number
62
Categorie Soggetti
Dermatology
Journal title
JOURNAL OF INVESTIGATIVE DERMATOLOGY SYMPOSIUM PROCEEDINGS
Photochemotherapy with 8-methoxypsoralen and long wavelength ultraviolet ra
diation (PUVA) is commonly used to treat psoriasis and vitiligo, These vast
ly different diseases respond to the therapy by different mechanisms even t
hough the immediate effects of the therapy photoadduct formation - is the s
ame for both. Because psoriasis is not cured by PUVA, patients receive many
treatments over their lifetime and develop a significant risk for the deve
lopment of skin cancers (primarily squamous cell carcinomas). In this revie
w the basic aspects of psoralen photobiology are reviewed briefly. In addit
ion the impact of the analysis of mutations in the tumor suppressor gene, p
53, are summarized. An unexpected mutation spectrum (very few T --> A trans
versions and frequent UVB signature C --> T transitions) suggest that effec
ts other than direct DNA photoadduct formation may be at play. The roles of
reactive oxygen species-induced base changes as well as other clastogenic
factors are discussed. This analysis suggests that it may be possible to im
prove the therapeutic efficacy of PUVA by a careful evaluation of the mode
of delivery.