Moracin treatment can inhibit the double 12-O-tetradecanoylphorbol 13-acetate (TPA) treatment-induced morphological changes reflecting inflammatory response, including leucocyte infiltration, hyperplasia and cell proliferation; moracin treatment furthermore can significantly suppress the elevation in 4-HNE level and elevate expression of c-fos, c-myc and cycloxygenase-2 (COX-2) in normal epidermis induced by double application of TPA; the moracin may be protective influence in tumor promotion, utilization of Moracin may open a new avenue in the treatment of tumerigenesis.