In our previous work, we screened out and cloned BRCAA1 gene (breast cancer associated antigen 1 gene) from breast cancer cell line MCF-7cells [AF208045, also called ARID4B (AT-rich interactive domain-containing protein 4B)], and identified its antigen epitope peptide SSKKQKRSHK[7,8]. Here, ARID4B is linked to breast cancer.