The present invention relates to a novel compound and its uses, which is an extract isolated and purified from Antrodia camphorate, in particular to 4-hydroxy-2,3 -dimethoxy-6-methyl-5(3,7,11-trimethyl-dodeca-2,6,10-trienyl)-cyclohex-2-- enone, and its use in tumor growth inhibition. The compound of the invention, which has never been discovered in Antrodia camphorate, can be applied in inhibiting the growth of cancer cells, such as breast cancer, hepatic cancer and prostate cancer; and be used as a pharmaceutical composition to inhibit the tumor growth; or further be applied in prevention of heart and blood vessel disease or dietary supplements for health needs through its antioxidant activity.