The present invention relates to adenine nucleotide translocator 2 (ANT2) siRNA (small interfering RNA) or ANT2 shRNA (short hairpin RNA) suppressing the expression of ANT2 gene expression and anticancer agent containing the same. Furthermore, the present invention relates to methods for treating breast cancers or stem cells of a breast cancer by treating the same with ANT2 siRNA or ANT2 shRNA. In addition, the invention provides a method for inhibiting metastasis of breast cancer cells with ANT2 siRNA or ANT2 shRNA.
