THE EFFECT OF ORAL QUERCETIN ON UVB-INDUCED TUMOR-GROWTH AND LOCAL IMMUNOSUPPRESSION IN SKH-1

The effects of quercetin (4%) on UVB-induced carcinogenesis and immuno suppression were studied in hairless SKH-1 mice exposed daily to suber ythemal UVB for 12/13 and 16/17 weeks. Macroscopic and microscopic exa minations showed that quercetin did not affect the onset and growth of UVB-induced non-melanoma skin tumors. Quercetin prevented the UV-indu ced suppression of the contact hypersensitivity (CHS) and the reductio n of the percentage of CD8-positive cells in spleen and lymph nodes. O ther immunological parameters were not affected. Thus, the results ind icate that oral intake of a high dose of quercetin does not prevent UV B-induced carcinogenesis, although it restores the skin-associated CHS response. (C) 1997 Elsevier Science Ireland Ltd.