PHARMACEUTICAL COMPOSITION FOR PREVENTING OR TREATING BREAST CANCER INCLUDING CRYSTALLINE POLYMORPH OF TETRAARSENIC HEXOXIDE, AND METHOD FOR PRODUCING SAME
The present invention relates to a pharmaceutical composition for preventing or treating breast cancer which includes tetraarsenic hexoxide in which a crystalline polymorph a(As4O6-a), of tetraarsenic hexoxide is 99 pcnt or higher, and to a method for producing the same. The composition of the present invention exhibits excellent effects of inhibiting the proliferation and metastasis of cancer cells, and thus can be usefully used as an anticancer agent.