Composition for preventing and treating breast cancer including selenopsammaplin A as active ingredients

Provided is a composition for the prevention and treatment of one or more cancers selected from the group consisting of breast cancer, liver cancer, and gastric cancer, the composition comprising selenopsammaplin A as active ingredients. The selenopsammaplin A and derivatives thereof of the present invention have been confirmed to exhibit excellent anticancer activity against breast cancer, liver cancer, and gastric cancer cells, and exhibit not only a strong effect of suppressing breast cancer growth compared to existing psammaplin A but also an excellent effect of suppressing the metastasis of breast cancer cells, and thus the selenopsammaplin A and derivatives thereof are expected to be effectively usable as a pharmaceutical composition for the prevention and treatment of breast cancer, liver cancer, and/or gastric cancer, and for the suppression of breast cancer metastasis.