The carcinogenicity (photocarcinogenicity) of sunlight to human skin has been recognized more than a century ago.
Last decades numerous experimental studies show that UV rays damage DNA, cause gene mutations leading to the development
of malignant tumors such basal cell carcinomas, squamous cell carcinomas and melanomas. The tumors occur
most frequently in fair skinned people, and the mutations typically are found at dipyrimidine sites with C-T or / and
CC-TT tandem double mutations. The authors briefly summarize their investigation of the p53 suppressor gene, and expose
their hypothesis of hTERT involvement in cancerogenesis. Also their underline the importance of UV induced
immunosuppression in photocarcinogenesis. Psoriatic patients are exposed to numerous cancerogens in their treatment.
A better understanding of the mechanisms of photocarcinogenesis could provide new ways in the treatment of skin tumors
