The present invention relates to a novel application of a compound. The compound 4-hydroxy-2,3-dimethoxy-6-methyl-5-(3,7,11-trimethyl-dodeca-2,6,10-trienyl)-cyclohex-2-enone of the invention is isolated and purified from the extracts of Antrodia camphorata, which can be applied for inhibiting the survival of skin cancer cells and be used as a pharmaceutical composition to inhibit the skin tumor growth.