The present invention relates to an application of isoobtusilactone A in preparation of medicine composition for treating breast cancer, in which a dose of 0.5-10&mgr；mol/L isoobtusilactone A is put in contact with breast cancer cells to kill breast cancer cells with cytotoxicity thereof. The present invention uses isoobtusilactone A extracted from Cinnamomum kotoense, which shows inhibition on human breast cancer cells MCF-7 and MDA-MB-231. The present invention induces arrest and apoptosis of breast cancer cells in cell cycles G2 and M to effectively inhibit the growth of cancer cells. The present invention provides a potential mechanism of isoobtusilactone A for chemotherapy of breast cancer. Further application can be made in human body of patient to confirm the inhibition of growth of breast cancer cells by isoobtusilactone A to provide a total combating effect against breast cancer.本發明係關於一種利用埃索奧比土西內酯A(isoobtusilactone A,IOA)在製備治療乳癌之醫藥組合物之應用，其中係使0．5至10μmol/L劑量的埃索奧比土西內酯A(isoobtusilactone A,IOA)與乳癌細胞接觸以毒殺乳癌細胞。本發明以台灣蘭嶼肉桂中萃取而成的埃索奧比土西內酯A(isoobtusilactone A,IOA)，其對於人類乳癌細胞株MCF－7和MDA－MB－231具有抑制作用。本發明誘導乳癌細胞在細胞週期G2及M期產生停滯和細胞凋亡以達到有效抑制癌細胞的生長。本發明提供了埃索奧比土西內酯A(isoobtusilactone A,IOA)在乳癌的化學治療可能的機轉。可更深入應用於人類病患體內以確認埃索奧比土西內酯A(isoobtusilactone A,IOA)對癌細胞生長抑制作用以全面性對抗乳癌的作用。
